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#!/usr/bin/perl -w
################################################################################
#
# PROGRAM: ccconfig
#
################################################################################
#
# DESCRIPTION: Get Convert::Binary::C configuration for a compiler.
#
################################################################################
#
# $Project: /Convert-Binary-C $
# $Author: mhx $
# $Date: 2011/04/10 12:32:12 +0200 $
# $Revision: 69 $
# $Source: /bin/ccconfig $
#
################################################################################
#
# Copyright (c) 2002-2011 Marcus Holland-Moritz. All rights reserved.
# This program is free software; you can redistribute it and/or modify
# it under the same terms as Perl itself.
#
################################################################################

use IO::File;
use Getopt::Long;
use Data::Dumper;
use strict;

my($NAME) = $0 =~ /([\w\.]+)$/;
my $VERSION = ('$Snapshot: /Convert-Binary-C/0.76 $' =~ /([^\/\s]+)\s*\$$/)[0];
my $MESSAGE = "\nThis is $NAME, v$VERSION ($0).\n";
my %OPT = (
  'output-format' => 'dumper',
);

unless( GetOptions( \%OPT, qw(
          cc|c=s inc-path|I=s@ basename=s
          output-file|o=s output-format|f=s
          preprocess=s compile-obj=s compile-exe=s
          obj-ext=s exe-ext=s c-ext=s pp-ext=s
          version debug quiet status! run! delete!
      ) ) ) {
  # poor man's pod2usage...
  my($USAGE) = do { local(@ARGV,$/)=($0); <> }
               =~ /^__END__.*?^=head\d\s+SYNOPSIS(.*?)^=/ms;
  my %M = ( 'I' => '*' );  # minimal markup
  $USAGE =~ s/([A-Z])<([^>]+)>/$M{$1}$2$M{$1}/g;
  $USAGE =~ s/^/    /gm;
  print STDERR "\nUsage:$USAGE",
               "Try `perldoc $NAME' for more information.\n\n";
  exit 2;
}

if( $OPT{version} ) {
  print <<VERSION;
$MESSAGE
Copyright (c) 2002-2011 Marcus Holland-Moritz. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

VERSION
  exit 0;
}

STDERR->autoflush(1);

$OPT{quiet} or print STDERR $MESSAGE, "\n";

my $output = \*STDOUT;

if (exists $OPT{'output-file'}) {
  $output = new IO::File ">$OPT{'output-file'}"
            or die "Cannot open $OPT{'output-file'}: $!\n";
}

my %format = (
  dumper  => sub {
               my $cfg = shift;
               local $Data::Dumper::Sortkeys = 1;
               return Data::Dumper->Dump([$cfg], ['*config']);
             },
  require => sub {
               my $cfg = shift;
               local $Data::Dumper::Indent = 1;
               local $Data::Dumper::Sortkeys = 1;
               my $dump = Data::Dumper->Dump([$cfg], ['config']);
               $dump =~ s/.*(?={)//;
               return $dump;
             },
);

unless (exists $format{$OPT{'output-format'}}) {
  my $valid = join ', ', sort keys %format;
  die <<EOM;
Invalid output format: '$OPT{'output-format'}'
Valid output formats are: $valid
EOM
}

my $cc  = new Compiler::Config %OPT, ccflags => [@ARGV];
my $cfg = $cc->get_config;
$cc->cleanup;

unless( $OPT{quiet} ) {
  my($wall, $usr, $sys, $cusr, $csys) = (time - $^T, times);
  my $cpu = sprintf "%.2f", $usr + $sys + $cusr + $csys;
  $usr = sprintf "%.2f", $usr + $cusr;
  $sys = sprintf "%.2f", $sys + $csys;
  print STDERR <<END;

Finished in $wall wallclock secs ($usr usr + $sys sys = $cpu CPU)

END
}

print $output $format{$OPT{'output-format'}}->($cfg);

exit 0;


package Compiler::Config;

use IO::File;
use Data::Dumper;
use Text::Wrap;
use Text::ParseWords;
use Carp;
use strict;

use constant SUCCESS     => 0;
use constant ERR_REQUIRE => 1;
use constant ERR_CREATE  => 2;
use constant ERR_CONFIG  => 3;

use constant UNKNOWN     => 0;
use constant GNU_GCC     => 1;
use constant INTEL_ICC   => 2;
use constant MS_VCPP     => 3;

my %type_map;

BEGIN {
  %type_map = (
    &MS_VCPP => { 'long long' => '__int64' }
  );
};

########################################################################
#
#  CONSTANT / AUTOGENERATED STUFF
#
########################################################################

sub ANSI_headers
{
  qw(
    assert.h  ctype.h  errno.h   float.h   limits.h
    locale.h  math.h   setjmp.h  signal.h  stdarg.h
    stddef.h  stdio.h  stdlib.h  string.h  time.h
  )
}

sub _preset_names
{
  qw(
    __386BSD__ __3dNOW__ __3dNOW_A__ __64BIT__ ____386BSD____ a29k ABI64
    ABIN32 ADDR64 aegis AES_SOURCE AIX AIX32 AIX370 AIX41 AIX42 AIX43 AIX51
    AIX64 AIX_SOURCE aixpc ALL_SOURCE alliant ALMOST_STDC alpha ALPHA_
    Alpha_AXP alpha_bwx alpha_cix alpha_ev4 alpha_ev5 alpha_ev6 alpha_fix
    alpha_max alpha_vxworks ALTIVEC AM29000 am29050 AM29K AM33 AM33_2 AMD64
    amiga AMIGAOS AMIX ansi ANSI_C_SOURCE ANSI_COMPAT AOUT APCS_26 APCS_32
    apollo APOLLO_SOURCE APPLE APPLE_CC APX386 arc arch64 arch_ arch__v3
    arch__v8 ARCH_COM ARCH_PPC ARCH_PPC64 ARCH_PWR ARCH_PWR2 arch_v10
    arch_v3 arch_v32 arch_v8 ARCHITECTURE ardent arm arm2 arm32 arm6
    ARM_ARCH_2 ARM_ARCH_3 ARM_ARCH_3M ARM_ARCH_4 ARM_ARCH_4T ARM_ARCH_5
    ARM_ARCH_5E ARM_ARCH_5T ARM_ARCH_5TE arm_elf arm_oabi ARMEB ARMEL
    ARMWEL atarist athlon athlon_sse att386 att3b AUX AUX_SOURCE AVR
    AVR_ARCH AVR_ASM_ONLY AVR_AT43USB320 AVR_AT43USB355 AVR_AT76C711
    AVR_AT90C8534 AVR_AT90S1200 AVR_AT90S2313 AVR_AT90S2323 AVR_AT90S2333
    AVR_AT90S2343 AVR_AT90S4414 AVR_AT90S4433 AVR_AT90S4434 AVR_AT90S8515
    AVR_AT90S8535 AVR_AT94K AVR_ATmega103 AVR_ATmega128 AVR_ATmega16
    AVR_ATmega161 AVR_ATmega163 AVR_ATmega32 AVR_ATmega323 AVR_ATmega603
    AVR_ATmega64 AVR_ATmega8 AVR_ATmega83 AVR_ATmega85 AVR_ATtiny11
    AVR_ATtiny12 AVR_ATtiny15 AVR_ATtiny22 AVR_ATtiny28 AVR_ENHANCED
    AVR_MEGA base BeOS BIG_ENDIAN BIGMODEL BIT_MSF bool BSD bsd43 bsd4_2
    BSD4_3 bsd4_4 BSD_4_3 BSD_4_4 BSD_C BSD_NET2 BSD_SOURCE BSD_TIME
    BSD_TYPES BSDCOMPAT bsdi BUFSIZ bull BULL_SOURCE BYTE_MSF BYTE_ORDER c
    C30 C31 C32 C33 C3x C40 C44 C4x cadmus CALL_AIX CALL_AIXDESC CALL_NT
    CALL_SYSV cdecl CHAR_UNSIGNED CLASSIFY_TYPE clipper CMU COFF COMPATMATH
    COMPILER_VERSION CONCURRENT CONIX convex convex_c1 convex_c2 convex_c32
    convex_c34 convex_c38 CONVEX_FLOAT_ CONVEX_SOURCE cplusplus CPU
    CPU_FAMILY CPU_VARIANT CRAY CRAYIEEE CRAYMPP CRAYT3E CRIS
    CRIS_ABI_version CRIS_arch_tune CRIS_arch_version ctix CX_UX CYGWIN
    CYGWIN32 D30V DCC DCE_THREADS DCPLUSPLUS declspec DGUX DGUX_SOURCE
    DGUX_TARGET DIAB_TOOL DJGPP dmert DOLPHIN DOUBLE_IS_32BITS DPX2 DSO
    DSP1600 DSP1610 DYNAMIC Dynix DynixPTX EABI ECOFF ELF elinux elxsi
    embedded EMBEDDED_CROSS encore EPI EXTENSIONS EXTERN_PREFIX FAVOR_BSD
    FILE_OFFSET_BITS FILENAME_MAX float128 float80 fpreg fr30 FreeBSD frv
    FRV_ACC FRV_DWORD FRV_FPR FRV_GPR FRV_HARD_FLOAT FRV_UNDERSCORE
    FRV_VLIW G_FLOAT gcc GCC_NEW_VARARGS gcos gcx GFLOAT gimpel GLIBC
    GLIBC_MINOR gmicro GNU GNU_CRIS gnu_hurd GNU_LIBRARY gnu_linux
    GNU_SOURCE GNUC GNUC_MINOR GNUC_PATCHLEVEL GO32 gould GOULD_PN
    GP_SUPPORT H3050R H3050RX H8300 H8300H H8300S hardfp HAVE_68881 HAVE_CE
    HAVE_FPA HAVE_FPU HAVE_SHORT_DOUBLE HAVE_SHORT_INT HAVE_SKY hbullx20
    hcx HITACHI HIUX_SOURCE host_mips hp200 hp300 hp64000 hp64902 hp64903
    HP700 hp800 hp9000 hp9000ipc hp9000s200 hp9000s300 hp9000s400
    hp9000s500 hp9000s700 hp9000s800 hp9k8 HP_aCC hp_osf hppa hpux HPUX_ASM
    HPUX_SOURCE hypersparc i186 i286 i370 i386 i486 i586 i686 i8086 I80960
    i860 i960 i960_CA i960_CC i960_CF i960_KA i960_KB i960_MC i960_SA
    i960_SB i960CA i960CC i960CF i960JA i960JD i960JF i960KA i960KB i960MC
    i960RP i960SA i960SB IA64 iAPX286 IBITS32 ibm ibm032 ibmesa IBMR2 ibmrt
    IEEE_FLOAT IEEE_FLOAT_ IEEE_FP IEEE_FP_INEXACT ILP32 ILP64
    INCLUDE__STDC__ INCLUDE_LONGLONG INLINE INLINE_INTRINSICS INT int128
    INT64 INT_MAX INTEL interdata INTERIX INTRINSICS IP2K is68k itanium
    IWMMXT ix86 k6 k6_2 k6_3 KPRINTF_ATTRIBUTE KR ksr1 LANGUAGE_ASSEMBLY
    LANGUAGE_C LANGUAGE_C_PLUS_PLUS LANGUAGE_OBJECTIVE_C LARGE_FILE_API
    LARGEFILE64_SOURCE LARGEFILE_SOURCE LD64 LDBL LE370 LFS64_LARGEFILE
    LFS_LARGEFILE lint Linux LITTLE_ENDIAN LITTLE_ENDIAN_DATA LONG64
    LONG_DOUBLE LONG_DOUBLE_128 LONG_DOUBLE_64 LONG_LONG LONG_LONG_MAX
    LONG_MAX LONGDOUBLE LONGLONG LP64 luna luna88k Lynx M210 M32R m32r2
    m32rx M340 m68 M68000 m68020 m68030 m68040 m68332 m68k m88000 m88100
    m88110 m88k M88KBCS_TARGET M_ALPHA M_BITFIELDS M_COFF M_I186 M_I286
    M_I386 M_I8086 M_I86 M_I86SM M_INTERNAT M_IX86 M_SDATA M_STEXT M_SYS3
    M_SYS5 M_SYSIII M_SYSV M_UNIX M_WORDSWAP M_XENIX MACH machine MachTen
    macII MASSCOMP MATH_HAS_NO_SIDE_EFFECTS MAVERICK MBCS mc300 mc500
    mc68000 mc68010 mc68020 mc68030 mc68040 mc68060 MC6811 MC6812 mc68302
    mc68332 mc68881 mc68hc11 mc68hc12 mc68hc1x mc68hcs12 mc68k mc68k32
    mc700 mc88000 mc88100 mc88110 mcf5200 MCORE MCORE__ALIGN_4
    MCORE_ALIGN_8 MCOREBE MCORELE mcpu32 merlin mert MINGW32 MiNT mips
    mips16 mips64 mips_eabi mips_fpr MIPS_FPSET MIPS_ISA MIPS_SIM
    mips_single_float mips_soft_float MIPS_SZINT MIPS_SZLONG MIPS_SZPTR
    MIPSEB MIPSEL MMIX MMIX_ABI_GNU MMIX_ABI_MMIXWARE MMX MN10200 MN10300
    MODERN_C moss motorola mpc505 mpc604 mpc750 mpc821 mpc860 mpeix MSC_VER
    MSDOS MSVCRT MT MTXINU MULTIMAX MULTITHREADED mvs n16 NATURAL_ALIGNMENT
    ncl_el ncl_mr NetBSD netware news1500 news1700 news1800 news1900
    news3700 news700 news800 news900 NeXT NEXT_SOURCE NLS NO_INLINE
    NO_INLINE_MATH NO_INLINE_STDLIB NO_INTERRUPTS NO_LEADING_UNDERSCORES
    NO_PROTOTYPE NO_UNDERSCORES NODE nofp nonstopux ns16000 ns32000 ns32016
    ns32332 ns32532 ns32k nsc32000 OCS88 OEMVS OPEN_NAMESPACE OpenBSD
    openedition OPENNT OPTIMIZE OS OS2 OS390 osf OSF1 OSF_SOURCE pa_risc
    PA_RISC1_1 PA_RISC2_0 PARAGON PARISC PC532 pdp11 pe pentium pentium2
    pentium3 pentium4 pentium__mmx pentiumpro PGC pic PIC_ pj plexus PORTAR
    POSIX POSIX1B_SOURCE POSIX2_SOURCE POSIX4_SOURCE POSIX_C_SOURCE
    POSIX_SOURCE POSIX_THREADS POWER PowerPC powerpc64 PPC ppc403 ppc601
    ppc602 ppc603 ppc603e PPC64 PPC64_ PPC_ PRAGMA_REDEFINE_EXTNAME pro
    PROTOTYPES ps2 psos PTHREAD_USE_D4 PTHREADS PTHREADS95 PTRDIFF_TYPE PWB
    pyr QNX R3000 R4000 REENTRANT REGPARM RELOCATABLE RES REVARGV Rhapsody
    rios RISC6000 riscbsd riscix riscos ROSE rs6000 RT rtasim rtems RTP
    s390 s390x s64_t SA110 SCO SCO_C_DIALECT SCO_COFF SCO_DS SCO_ELF
    SCO_ODS_30 SCO_XPG_VERS score3 scs semi sequent SEQUENT_ sgi SGI_SOURCE
    sh sh1 sh2 sh3 SH3E SH4 SH4_100 SH4_200 SH4_300 SH4_340 SH4_400 SH4_500
    SH4_NOFPU SH4_SINGLE SH4_SINGLE_ONLY SH5 SHARED SHMEDIA SHRT_MAX
    simulator sinix SIZE_INT SIZE_LONG SIZE_PTR SIZE_TYPE SNI SOCKET_SOURCE
    SOCKETS_SOURCE SOFT_FLOAT SOFTFP SOLARIS_THREADS sony sony_news
    sonyrisc sparc sparc64 sparc_v8 sparc_v9 sparclet sparclite
    sparclite86x sparcv9 spectrum spur SSE SSE2 stardent STATIC
    STD_INCLUDE_DIR STDC STDC_EXT STDC_HOSTED STDC_VERSION stdcall STDCPP
    stratos STRICT_ANSI STRICT_BSD STRICT_NAMES sun sun3 sun386 Sun386i
    supersparc SVID SVR3 SVR4 SVR4_2 SVR4_ABI SVR4_SOURCE svr5 SX system
    SYSTYPE_BSD SYSTYPE_BSD43 SYSTYPE_BSD44 SYSTYPE_SVR4 SYSTYPE_SVR5
    SYSTYPE_SYSV SYSV SYSV3 SYSV4 SYSV5 sysV68 sysV88 SYSV_SOURCE tahoe
    Tek4132 Tek4300 THREAD_SAFE THREADS_POSIX4ad4 thumb THUMB_INTERWORK
    THUMBEB THUMBEL titan TM3200 TM5400 TM5600 TMS320C30 TMS320C31
    TMS320C32 TMS320C33 TMS320C3x TMS320C40 TMS320C44 TMS320C4x tower
    tower32 tower32_200 tower32_600 tower32_700 tower32_800 tower32_850
    TOWER_ASM tss tune_ tune_athlon tune_athlon_sse tune_i386 tune_i486
    tune_i586 tune_i686 tune_k6 tune_k6_2 tune_k6_3 tune_pentium
    tune_pentium2 tune_pentium3 tune_pentium4 tune_pentium_mmx
    tune_pentiumpro tune_v tune_v10 tune_v3 tune_v8 u370 u3b u3b2 u3b20
    u3b200 u3b20d u3b5 u64_t uclinux UINT128_T ultrix UMAXV unaligned
    UnicomPBB UnicomPBD UNICOS UNICOSMK unix UNIX95 UNIX99 unixpc unos
    USE_BSD USE_FILE_OFFSET64 USE_GNU USE_INIT_FINI USE_ISOC9X
    USE_LARGEFILE USE_LARGEFILE64 USE_MISC USE_POSIX USE_POSIX199309
    USE_POSIX199506 USE_POSIX2 USE_REENTRANT USE_RTC USE_SVID USE_UNIX98
    USE_XOPEN USE_XOPEN_EXTENDED USES_INITFINI USG USGr4 USGr4_2 UTek Utek
    UTS UWIN uxpm uxps v20 v33 v850 v850e v850e1 v850ea v851 vax venix
    VMESA VMS VSTA VTHREADS vxworks vxworks_5 wchar_t WCHAR_TYPE we32000
    WIN32 WINNT WINT_TYPE WRS_R3K_EXC_SUPPORT X86_ x86_64 X_FLOAT xenix
    Xenix286 XOPEN_C XOPEN_SOURCE XOPEN_SOURCE_EXTENDED XPG2 XPG2_EXTENDED
    XPG3 XPG3_EXTENDED XPG4 XPG4_EXTENDED XSCALE xstormy16 XTENSA XTENSA_EB
    XTENSA_EL XTENSA_SOFT_FLOAT z8000
  )
}

sub _assert
{
  {
    'cpu' => [qw(
      a29k alpha arc arm bwx cix clipper convex elxsi ev4 ev5 ev6 fix h8300
      h8300h h8300s hppa i370 i386 i860 i960 ia64 ibm032 m32r m68k m88k max
      mc68000 mc68020 mc68030 mc68040 mips ns32k parisc powerpc powerpc64
      pyr rs6000 sh sparc sparc64 spur tahoe tron v850 vax we32000 x86_64
      xtensa
    )],
    'endian' => [qw(
      big little
    )],
    'lint' => [qw(
      off
    )],
    'machine' => [qw(
      a29k alpha arc arm bigendian clipper convex d30v elxsi fr30 h8300
      h8300h h8300s hppa i370 i386 i860 i960 ia64 ibm032 littleendian m32r
      m68k m88k macII mc68000 mips ns32k parisc powerpc powerpc64 pyr
      rs6000 sgi sh sparc sparc64 sparcv9 spur tahoe tron v850 vax we32000
      x86_64 xstormy16 xtensa
    )],
    'model' => [qw(
      ilp32 lp64
    )],
    'system' => [qw(
      aix AUX beos bsd embedded FreeBSD gnu hiux hpux hurd interix linux
      lynx mach msdos mvs NetBSD netware OpenBSD openedition osf1 posix
      ptx4 rtems simulator svr3 svr4 unix vms vsta vxworks winnt xpg4
    )]
  }
}

########################################################################
#
#  CONSTRUCTOR
#
########################################################################

sub new
{
  my $class = shift;
  my $self = bless {
    'headers'     => [&ANSI_headers],
    'ppline'      => qr/^\s*#\s*(?:line\s*)?(\d+)\s*"([^"]*)"/,   # TODO: make configurable?
    'debug'       => 0,
    'quiet'       => 0,
    'status'      => 1,
    'run'         => 1,
    'delete'      => 1,
    'timeout'     => 30,
    'basename'    => '_t_e_s_t',
    'c-ext'       => '.c',
    @_
  }, $class;

  $self->{fatal} = 0;
  $self->{__int__} = 0;

  $SIG{INT} = sub { $self->{__int__} = 1; $SIG{INT} = 'DEFAULT' };

  $self->_configure;

  $self->{fatal} = 1;

  $self;
}

########################################################################
#
#  CONFIGURATION
#
########################################################################

sub _getwarn
{
  my @warn = @_;

  for( @warn ) {
    s/\s+at\s+\Q$0\E\s+line\s+\d+\.//m;
    s/^\s*included\s+from\s+\[buffer\]:\d+[\r\n]+//m;
    s/[\r\n]+$//;
  };

  @warn;
}

sub check_config
{
  my $self    = shift;
  my $config  = shift;
  my @headers = @_;
  my %inc;

  eval { require Convert::Binary::C };
  $@ and return {code => ERR_REQUIRE};

  $self->{debug} and import Convert::Binary::C debug => 'all';

  my $c = eval { new Convert::Binary::C };
  $@ and return {code => ERR_CREATE};

  eval { $c->configure( %$config ) };
  $@ and return {code => ERR_CONFIG};

  @inc{@headers} = (undef) x @headers;

  my %res = (
    code     => SUCCESS,
    header   => \%inc,
    fail     => [],
    succ     => [],
    warnings => [],
  );

  for my $hdr ( keys %inc ) {
    my $code = "#include <$hdr>\n";
    my @warn;
    {
      local $^W = 1;
      local $SIG{__WARN__} = sub { push @warn, @_ };
      eval { $c->clean->parse( $code ) };
    }
    $inc{$hdr} = { warnings => [_getwarn(@warn)] };
    push @{$res{warnings}}, _getwarn(@warn);
    if( $@ ) {
      ($inc{$hdr}{error}) = _getwarn($@);
      push @{$res{fail}}, $hdr;
    }
    else {
      push @{$res{succ}}, $hdr;
    }
  }

  return \%res;
}

sub get_config
{
  my $self = shift;
  exists $self->{config} or $self->run_checks;

  my @headers;
  my @missing;

  $self->_msg( "\nChecking for ANSI headers..." );

  for my $hdr ( @{$self->{headers}} ) {
    my $found = 0;
    for my $inc ( @{$self->{'inc-path'}} ) {
      if( -e $inc.$hdr ) {
        $found = 1;
        last;
      }
    }
    push @{ $found ? \@headers : \@missing }, $hdr;
  }

  if( @missing ) {
    $self->_msg("The following ANSI headers are missing:");
    $self->_wrapped_list( @missing );
  }
  else {
    $self->_msg("All ANSI headers found.");
  }

  $self->_msg( "\nAssembling the configuration..." );

  my %predef = %{$self->{predefined} || {}};
  my %def;
  my $compiler = $self->_compiler;

  if( $compiler == GNU_GCC ) {
    $self->_msg( "You're using the GNU compiler." );
    %def = (
      '__attribute(x)'    => '',
      '__attribute__(x)'  => '',
      '__typeof(x)'       => 'int',
      '__typeof__(x)'     => 'int',
      '__alignof(x)'      => '1',
      '__alignof__(x)'    => '1',
      '__label__'         => 'int',
      '__builtin_va_list' => 'int',
    );
  }
  elsif( $compiler == INTEL_ICC ) {
    $self->_msg( "You're using the Intel compiler." );
    %def = (
      '__attribute(x)'    => '',
      '__attribute__(x)'  => '',
      '__typeof(x)'       => 'int',
      '__typeof__(x)'     => 'int',
      '__alignof(x)'      => '1',
      '__alignof__(x)'    => '1',
      '__label__'         => 'int',
      '__builtin_va_list' => 'int',
    );
  }
  elsif( $compiler == MS_VCPP ) {
    $self->_msg( "You're using the Microsoft compiler." );
    $def{'__int64'} = 'long long';
  }

  if( exists $predef{__CYGWIN__} || exists $predef{_WIN32} ) {
    $self->_msg( "This is a Windows compiler." );
    $def{'__cdecl'} = '';
    $def{'__declspec(x)'} = '';
  }

  my %cfg;
  my $define = sub { [ map { "$_=$predef{$_}" } sort keys %{$_[0]} ] };

  if( exists $self->{basic_sizes} ) {
    my %sizes = %{$self->{basic_sizes}};
    my %valid = (
                  PointerSize    => [    0, 1, 2, 4, 8        ],
                  EnumSize       => [-1, 0, 1, 2, 4, 8        ],
                  IntSize        => [    0, 1, 2, 4, 8        ],
                  CharSize       => [    0, 1, 2, 4, 8        ],
                  ShortSize      => [    0, 1, 2, 4, 8        ],
                  LongSize       => [    0, 1, 2, 4, 8        ],
                  LongLongSize   => [    0, 1, 2, 4, 8        ],
                  FloatSize      => [    0, 1, 2, 4, 8, 12, 16],
                  DoubleSize     => [    0, 1, 2, 4, 8, 12, 16],
                  LongDoubleSize => [    0, 1, 2, 4, 8, 12, 16],
                );

    for my $type ( keys %sizes ) {
      my $opt = join( '', map ucfirst, split ' ', $type ) . 'Size';
      if( exists $valid{$opt} ) {
        if( grep { $sizes{$type} == $_ } @{$valid{$opt}} ) {
          $cfg{$opt} = $sizes{$type};
        }
        else {
          $self->_msg( "Strange size '$sizes{$type}' for type '$type'." );
        }
      }
      else {
        $self->_msg( "Strange type '$type' with size '$sizes{$type}'." );
      }
    }
  }

  if( exists $self->{unsigned_chars} and defined $self->{unsigned_chars} ) {
    $cfg{UnsignedChars} = $self->{unsigned_chars};
  }
  if( exists $self->{alignment} and defined $self->{alignment} ) {
    if( grep { $self->{alignment} == $_ } 1, 2, 4, 8, 16 ) {
      $cfg{Alignment} = $self->{alignment};
    }
    else {
      $self->_msg( "Strange alignment '$self->{alignment}'." );
    }
  }
  if( exists $self->{compound_alignment} and defined $self->{compound_alignment} ) {
    if( grep { $self->{compound_alignment} == $_ } 1, 2, 4, 8, 16 ) {
      $cfg{CompoundAlignment} = $self->{compound_alignment};
    }
    else {
      $self->_msg( "Strange compound alignment '$self->{compound_alignment}'." );
    }
  }
  if( exists $self->{invalid_keywords} and @{$self->{invalid_keywords}} > 0 ) {
    $cfg{DisabledKeywords} = $self->{invalid_keywords};
  }
  if( exists $self->{keyword_map} and keys %{$self->{keyword_map}} > 0 ) {
    $cfg{KeywordMap} = $self->{keyword_map};
  }
  if( exists $self->{byteorder} and $self->{byteorder} ) {
    $cfg{ByteOrder} = $self->{byteorder};
  }
  if( exists $self->{cpp_comments} ) {
    $cfg{HasCPPComments} = $self->{cpp_comments};
  }
  if( exists $self->{stdc_version} ) {
    $cfg{StdCVersion} = $self->{stdc_version};
  }
  if( exists $self->{stdc_hosted} ) {
    $cfg{HostedC} = $self->{stdc_hosted};
  }
  if( exists $self->{'inc-path'} and @{$self->{'inc-path'}} > 0 ) {
    $cfg{Include} = [ map { s/[\\\/]+$//; $_ } @{$self->{'inc-path'}} ];
  }

  keys %{$self->{preasserted}} and $cfg{Assert} = [sort keys %{$self->{preasserted}}];

  unless (keys %cfg) {
    $self->_msg("\nI could not get any useful compiler information.");
    $self->_quit;
  }

  $self->_msg( "\nTesting configuration..." );

  $self->_debug(sub { Data::Dumper->Dump( [\%def, \%predef, \%cfg], [qw(*def *predef *cfg)] ) });

  # First, check if the configuration works without additional defines

  my $warnings = 0;
  my $failures = 0;
  keys %predef and $cfg{Define} = $define->( \%predef );

  my $res = $self->check_config( \%cfg, @headers );
  $self->_debug(sub { Data::Dumper->Dump( [$res], [qw(res)] ) });

  if( $res->{code} == SUCCESS ) {
    $failures = @{$res->{fail}};
    $warnings = @{$res->{warnings}};
    if( $failures ) {
      $self->_msg( "Plain configuration failed for these headers:" );
      $self->_wrapped_list( sort @{$res->{fail}} );
    }
    else {
      if( $warnings == 0 ) {
        goto finish;
      }
      $self->_msg( "Plain configuration works fine, but there are some warnings:" );
      $self->_out( "| ", @{$res->{warnings}} );
    }
  }
  else {
    goto finish;
  }

  # There were errors or warnings. Let's see if there's something we can try...

  unless( keys %def ) {
    if( $res->{code} == SUCCESS ) {
      $self->_msg( "\nHowever, there's nothing I can do about it." );
    }
    goto finish;
  }

  $self->_msg( "\nI will try to add couple of defines..." );

  for my $key ( keys %def ) {
    my($name) = $key =~ /(\w+)/;
    delete $predef{$name};
    $predef{$key} = $def{$key};
  }

  keys %predef and $cfg{Define} = $define->( \%predef );

  my $newres = $self->check_config( \%cfg, @headers );
  $self->_debug(sub { Data::Dumper->Dump( [$res], [qw(res)] ) });

  if( $res->{code} != SUCCESS ) {
    $res = $newres;
    goto finish;
  }

  if( @{$newres->{fail}} < $failures  or
      @{$newres->{fail}} == $failures && @{$newres->{warnings}} < $warnings ) {
    $self->_msg( "This configuration feels better." );
    if( $failures ) {
      if( @{$newres->{fail}} ) {
        $self->_msg( "Only these headers still fail:" );
        $self->_wrapped_list( sort @{$newres->{fail}} );
      }
      else {
        $self->_msg( "No more headers that fail." );
      }
    }
    $res = $newres;
    $failures = @{$res->{fail}};
    $warnings = @{$res->{warnings}};
  }
  else {
    if( $failures == 0 and @{$newres->{fail}} > 0 ) {
      $self->_msg( "Whoa, now it fails. Restoring original configuration." );
    }
    else {
      $self->_msg( "Doesn't help. Restoring original configuration." );
    }
    goto finish;
  }

  # Try to remove as many defines as possible

  $self->_msg( "\nNow let's see which defines aren't neccessary..." );

  my %orgdef = %{$self->{predefined}};
  my @additional;
  my $tested = 0;

  for my $key ( sort keys %def ) {
    my($name) = $key =~ /(\w+)/;
    delete $predef{$key};
    exists $orgdef{$name} and $predef{$name} = $orgdef{$name};

    keys %predef and $cfg{Define} = $define->( \%predef );

    $newres = $self->check_config( \%cfg, @headers );
    $self->_debug(sub { Data::Dumper->Dump( [$res], [qw(res)] ) });

    if( $newres->{code} == SUCCESS and @{$newres->{fail}} <= $failures
                                   and @{$newres->{warnings}} <= $warnings ) {
      $res = $newres;
      $failures = @{$res->{fail}};
      $warnings = @{$res->{warnings}};
    }
    else {
      push @additional, $name;
      delete $predef{$name};
      $predef{$key} = $def{$key};
    }

    $self->_work_in_progress( sprintf "%d/%d needed", scalar @additional, ++$tested );
  }

  $self->_work_done;

  if( @additional ) {
    $self->_msg( "Additionally defining the following symbols:" );
    $self->_wrapped_list( sort @additional );
  }
  else {
    $self->_msg( "Not defining any additional symbols." );
  }

finish:
  if( $res->{code} == SUCCESS ) {
    if( @{$res->{succ}} > 0 ) {
      $self->_msg( "\n>>>>>>>>>> Successfully tested configuration! <<<<<<<<<<" );
    }
    else {
      $self->_msg( "\n>>>>>>>>>> Configuration test FAILED! <<<<<<<<<<" );
    }

    if( @{$res->{fail}} ) {
      $self->_msg( "\nThese headers fail:" );
      for my $hdr ( sort keys %{$res->{header}} ) {
        exists $res->{header}{$hdr}{error} or next;
        $self->_msg( "  <$hdr> $res->{header}{$hdr}{error}" );
      }
    }
    elsif( @{$res->{warnings}} ) {
      $self->_msg( "\nHowever, there are some warnings that I can't get rid of:" );
      $self->_out( "| ", @{$res->{warnings}} );
    }

    if( defined $self->{float_format} ) {
      if( $self->{float_format} eq 'IEEE' ) {
        Convert::Binary::C::feature('ieeefp') or $self->_msg( <<ENDMSG );

ATTENTION: The floating point format used by the tested compiler
           appears to be IEEE, but Convert::Binary::C was built
           without the 'ieeefp' feature. Don't try to handle
           any floating point values in this configuration.
ENDMSG
      }
      elsif( $self->{float_format} eq 'native' ) {
        Convert::Binary::C::feature('ieeefp') and $self->_msg( <<ENDMSG );

ATTENTION: The tested compiler does not seem to use IEEE floating
           point format. Instead, the format I found was compatible
           with the floating point format used natively by your
           machine. For some reason, Convert::Binary::C was built
           with the 'ieeefp' feature, which is not very clever if
           my tests were correct. However, don't try to handle any
           floating point values in this configuration.
ENDMSG
      }
      else {
        $self->_msg( <<ENDMSG );

ATTENTION: The tested compiler does not seem to use IEEE floating
           point format, nor does it seem to use a format compatible
           with the floating point format used natively by your
           machine. Don't try to handle any floating point values
           with Convert::Binary::C in this configuration.
ENDMSG
      }
    }
  }
  else {
    $res->{code} == ERR_REQUIRE and
      $self->_msg( "Failed to load Convert::Binary::C, cannot test configuration." );
    $res->{code} == ERR_CREATE and
      $self->_msg( "Could not create Convert::Binary::C object." );
    $res->{code} == ERR_CONFIG and
      $self->_msg( "Could not configure Convert::Binary::C object." );
  }

  keys %predef and $cfg{Define} = $define->( \%predef );

  return \%cfg;
}

########################################################################
#
#  COMPILER TESTING
#
########################################################################

sub cleanup
{
  my $self = shift;
  if( $self->{'delete'} ) {
    for( qw( c pp obj exe ) ) {
      my $meth = "_${_}file";
      my $file = $self->$meth();
      -e $file and unlink $file;
    }
    for( glob "$self->{basename}.*" ) { -e and unlink }
  }
}

sub run_checks
{
  my $self = shift;
  my $asserts;

  if ($self->{'inc-path'}) {
    for (@{$self->{'inc-path'}}) {
      $_ .= _OS('file-sep') unless /[:\/\\]$/
    }
  }
  elsif ($self->{can_read_ppout}) {
    $self->{'inc-path'} = $self->_run_incpath;
  }
  else {
    $self->{'inc-path'} = [];
  }

  ($self->{names}, $asserts)  = $self->_names( $self->{'inc-path'} );

  if ($self->{can_preprocess}) {
    $self->{predefined}         = $self->_get_predefined( $self->{names} );
    $self->{preasserted}        = $self->_get_preasserted( $asserts );
    $self->{stdc_version}       = delete $self->{predefined}{__STDC_VERSION__};
    $self->{stdc_hosted}        = delete $self->{predefined}{__STDC_HOSTED__};

    $self->{stdc_version} =~ s/L$// if defined $self->{stdc_version};
  }

  if ($self->{can_compile} || $self->{can_run}) {
    $self->{invalid_keywords}   = $self->_get_invalid_keywords;
    $self->{keyword_map}        = $self->_get_keyword_map;
    $self->{cpp_comments}       = $self->_get_cpp_comments;

    $self->{basic_sizes}        = $self->_get_basic_sizes;
    $self->{byteorder}          = $self->_get_byteorder;
    $self->{unsigned_chars}     = $self->_get_unsigned_chars;
    $self->{alignment}          = $self->_get_alignment;
    $self->{compound_alignment} = $self->_get_compound_alignment;

    # run _after_ byteorder test
    $self->{float_format}       = $self->_get_float_format;
  }
}

sub _compiler
{
  my $self = shift;

  exists $self->{predefined}{__GNUC__}         and return GNU_GCC;

  exists $self->{predefined}{__ICC} ||
  exists $self->{predefined}{__INTEL_COMPILER} and return INTEL_ICC;

  exists $self->{predefined}{_MSC_VER}         and return MS_VCPP;

  return UNKNOWN;
}

sub _test_type
{
  my($self, $type, $init, $width) = @_;

  my $begin = "\x21\x05\x19\x77*MHXCBC*\xDE\xAD\xBE\xEF";
  my $end   = "\x21\x05\x19\x77*MARCUS*\xDE\xAD\xBE\xEF";

  my $cvt = sub { join ', ', map { sprintf "0x%02X", $_ } unpack "C*", $_[0] };

  my $c_begin = $cvt->( $begin );
  my $c_end   = $cvt->( $end );

  $self->_temp( <<ENDC );
struct _t_e_s_t_ {
  unsigned char _a_[16];
  $type _x_;
  unsigned char _z_[16];
} _g_x = {
  { $c_begin },
  $init,
  { $c_end }
};
ENDC

  my $res = $self->_compile_temp;
  $res->{status} and return undef;

  my $fh = new IO::File $self->_objfile or return undef;
  binmode $fh;

  my $obj = do { local $/; <$fh> };

  $obj =~ /\Q$begin\E(.{1,$width}?)\Q$end\E/s and return $1;

  return undef;
}

#-----------------------------------------------------------------------
#  FLOATING POINT FORMAT
#-----------------------------------------------------------------------

sub _get_float_format_run
{
  my $self = shift;
  my $value = shift;
  my %res;

  TYPE: for my $type ( qw( float double ) ) {
    $self->_work_in_progress;

    $self->_temp( <<ENDC );
#include <stdio.h>
union fp {
  $type val;
  unsigned char byte[sizeof($type)];
};
int main()
{
  union fp x;
  int i;
  x.val = $value;
  printf("size=%d:", sizeof($type));
  for( i=0; i<sizeof($type); ++i )
    printf(" 0x%02X", (unsigned int) x.byte[i]);
  printf("\\n");
  return 0;
}
ENDC

    my $res = $self->_build_temp;

    if( -e $self->_exefile ) {
      local $self->{fatal} = 0;
      $res = $self->_run_temp;
    }
    else {
      $self->_msg( "Got no output from compiler for '($type) $value'." );
      next;
    }

    if( $res->{didnotrun} or $res->{status} ) {
      $self->_msg( "It seems I cannot run your compiler's executables." );
      last;
    }

    for my $line ( @{$res->{stdout}} ) {
      if( my($size, $hex) = $line =~ /^size=(\d+):\s*(.*)/ ) {
        my $bits = pack 'C*', map hex, $hex =~ /0x(\S{2})/g;
        length($bits) == $size or last;
        $res{$type} = $bits;
        next TYPE;
      }
    }

    $self->_msg( "Strange output for '($type) $value'" );
  }

  return \%res;
}

sub _get_float_format_compile
{
  my $self = shift;
  my $value = shift;
  my %res;

  for my $type ( qw( float double ) ) {
    $self->_work_in_progress;

    $res{$type} = $self->_test_type( $type, $value, 32 );

    unless( defined $res{$type} ) {
      $self->_msg( "Got no output from compiler for '($type) $value'." );
    }
  }

  return \%res;
}

sub _get_float_format
{
  my $self = shift;

  $self->_msg( "\nTrying to determine floating point format..." );

  my @test = (
    {
      value  => '-1.0',
      double => pack( 'C*', 0xBF, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ),
      single => pack( 'C*', 0xBF, 0x80, 0x00, 0x00 ),
    },
    {
      value  => '0.0',
      double => pack( 'C*', 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ),
      single => pack( 'C*', 0x00, 0x00, 0x00, 0x00 ),
    },
    {
      value  => '0.4',
      double => pack( 'C*', 0x3F, 0xD9, 0x99, 0x99, 0x99, 0x99, 0x99, 0x9A ),
      single => pack( 'C*', 0x3E, 0xCC, 0xCC, 0xCD ),
    },
    {
      value  => '1.0',
      double => pack( 'C*', 0x3F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ),
      single => pack( 'C*', 0x3F, 0x80, 0x00, 0x00 ),
    },
    {
      value  => '3.1415926535',
      double => pack( 'C*', 0x40, 0x09, 0x21, 0xFB, 0x54, 0x41, 0x17, 0x44 ),
      single => pack( 'C*', 0x40, 0x49, 0x0F, 0xDB ),
    },
    {
      value  => '1.220703125e-4',
      double => pack( 'C*', 0x3F, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ),
      single => pack( 'C*', 0x39, 0x00, 0x00, 0x00 ),
    },
  );

  my $meth = $self->{can_run} ? "_get_float_format_run" : "_get_float_format_compile";

  for my $t ( @test ) {
    my $res = $self->$meth( $t->{value} );
    $t->{result}{single} = $res->{float};
    $t->{result}{double} = $res->{double};
  }

  my $fail_nat = 0;
  my $fail_i3e = 0;
  my @tests;

  for my $t ( @test ) {
    my $s_nat = pack 'f', $t->{value};
    my $d_nat = pack 'd', $t->{value};
    my $s_i3e = $t->{single};
    my $d_i3e = $t->{double};

    if( defined $self->{byteorder} && $self->{byteorder} eq 'LittleEndian' ) {
      $_ = reverse $_ for $s_i3e, $d_i3e;
    }

    if( defined $t->{result}{single} ) {
      push @tests, { value => $t->{value}, format => 'single', ieee => $s_i3e,
                     native => $s_nat, got => $t->{result}{single} };
      $t->{result}{single} eq $s_nat or $fail_nat++;
      $t->{result}{single} eq $s_i3e or $fail_i3e++;
    }
    if( defined $t->{result}{double} ) {
      push @tests, { value => $t->{value}, format => 'double', ieee => $d_i3e,
                     native => $d_nat, got => $t->{result}{double} };
      $t->{result}{double} eq $d_nat or $fail_nat++;
      $t->{result}{double} eq $d_i3e or $fail_i3e++;
    }
  }

  $self->_work_done;

  my $fp_format;

  if( @tests == 0 ) {
    $self->_msg( "Could not determine floating point format." );
  }
  elsif( $fail_i3e == 0 ) {
    $fp_format = 'IEEE';
    $self->_msg( "Seems to be IEEE floating point format." );
  }
  elsif( $fail_nat == 0 ) {
    $fp_format = 'native';
    $self->_msg( "No IEEE, but at least the natively supported floating point format." );
  }
  else {
    $fp_format = 'unknown';
    $self->_msg( "Neither IEEE nor natively supported floating point format." );
    $self->_msg( "\nFYI, this is what I got:" );
    $self->_msg( "\nvalue           format  IEEE representation      Native representation    Compiler representation" );
    $self->_msg( '-'x97 );
    my $hex = sub { join ' ', map { sprintf "%02X", $_ } unpack "C*", $_[0] };
    for my $t ( @tests ) {
      $self->_msg( sprintf( "%-15s %-7s %-24s %-24s %-24s", $t->{value}, $t->{format},
                            $hex->($t->{ieee}), $hex->($t->{native}), $hex->($t->{got}) ) );
    }
    $self->_msg( '-'x97 );
  }

  return $fp_format;
}

#-----------------------------------------------------------------------
#  ALIGNMENT
#-----------------------------------------------------------------------

sub _get_alignment_run
{
  my $self = shift;
  my $type = shift;

  $self->_work_in_progress;

  $self->_temp( <<ENDC );
#include <stdio.h>
#include <stddef.h>
struct align {
  char a;
  $type b;
};
int main()
{
  printf("align=%d\\n", offsetof(struct align, b));
  return 0;
}
ENDC

  my $res = $self->_build_temp;

  if( -e $self->_exefile ) {
    local $self->{fatal} = 0;
    $res = $self->_run_temp;
  }
  else {
    $self->_work_done;
    $self->_msg( "Got no output from compiler for '$type'." );
    return undef;
  }

  if( $res->{didnotrun} or $res->{status} ) {
    $self->_work_done;
    $self->_msg( "It seems I cannot run your compiler's executables." );
    return undef;
  }

  for my $line ( @{$res->{stdout}} ) {
    $line =~ /^align=(\d+)/ and return $1;
  }

  $self->_work_done;
  $self->_msg( "Strange output..." );
  return undef;
}

sub _get_alignment_compile
{
  my $self = shift;
  my $type = shift;

  $self->_work_in_progress;

  my $init = $type =~ /(struct|union)\s+(\w+)/
                      ? "{ sizeof(struct align) - sizeof($1 $2) }"
                      : "{ sizeof(struct align) - sizeof($type), ($type) -1 }";

  my $res = $self->_test_type( "struct align { char a; $type b; }", $init, 32 );

  unless( defined $res ) {
    $self->_work_done;
    $self->_msg( "Got no output from compiler for '$type'." );
    return undef;
  }

  my $off = unpack "C", $res;

  if( $off == 0 ) {
    $self->_work_done;
    $self->_msg( "Strange output..." );
    return undef;
  }

  return $off;
}

sub _get_alignment
{
  my $self = shift;

  $self->_msg( "\nTrying to determine struct member alignment..." );

  my $meth = $self->{can_run} ? "_get_alignment_run" : "_get_alignment_compile";
  my $align;

  my $compiler = $self->_compiler;

  for my $type ( 'int', 'short', 'long', 'long long', 'float', 'double', 'int *' ) {
    my $real_type = $type_map{$compiler}{$type} || $type;
    if( defined( my $rv = $self->$meth( $real_type ) ) ) {
      !defined($align) || $rv > $align and $align = $rv;
    }
  }

  $self->_work_done;

  if( defined $align ) {
    $self->_msg( "Struct members are aligned to $align-byte boundaries." );
  }
  else {
    $self->_msg( "Could not determine struct member alignment." );
  }

  return $align;
}

sub _get_compound_alignment
{
  my $self = shift;

  $self->_msg( "\nTrying to determine compound alignment..." );

  my $meth = $self->{can_run} ? "_get_alignment_run" : "_get_alignment_compile";
  my $s_align = $self->$meth("struct testit { char a; }");
  my $u_align = $self->$meth("union testit { char a; }");

  $self->_work_done;

  if( defined($s_align) && defined($u_align) && $s_align == $u_align ) {
    $self->_msg( "Compounds are aligned to $s_align-byte boundaries." );
    return $s_align;
  }
  else {
    $self->_msg( "Could not determine compound alignment." );
    return undef;
  }
}

#-----------------------------------------------------------------------
#  BASIC TYPE SIZES
#-----------------------------------------------------------------------

sub _get_basic_sizes_run
{
  my $self = shift;
  my $type = shift;

  $self->_work_in_progress;

  $self->_temp( <<ENDC );
#include <stdio.h>
typedef $type _t_y_p_e_;
int main()
{
  printf("sizeof=%d\\n", sizeof(_t_y_p_e_));
  return 0;
}
ENDC

  my $res = $self->_build_temp;

  if( -e $self->_exefile ) {
    local $self->{fatal} = 0;
    $res = $self->_run_temp;
  }
  else {
    $self->_work_done;
    $self->_msg( "Got no output from compiler for '$type'." );
    return undef;
  }

  if( $res->{didnotrun} or $res->{status} ) {
    $self->_work_done;
    $self->_msg( "It seems I cannot run your compiler's executables." );
    return undef;
  }

  for my $line ( @{$res->{stdout}} ) {
    $line =~ /^sizeof=(\d+)/ and return $1;
  }

  $self->_work_done;
  $self->_msg( "Strange output..." );
  return undef;
}

sub _get_basic_sizes_compile
{
  my $self = shift;
  my $type = shift;

  $self->_work_in_progress;

  my $res = $self->_test_type( $type, "0", 16 );

  unless( defined $res ) {
    $self->_work_done;
    $self->_msg( "Got no output from compiler for '$type'." );
    return undef;
  }

  return length $res;
}

sub _get_basic_sizes
{
  my $self = shift;

  $self->_msg( "\nTrying to determine basic type sizes..." );

  my $meth = $self->{can_run} ? "_get_basic_sizes_run" : "_get_basic_sizes_compile";

  my %sizes;
  my $compiler = $self->_compiler;

  for my $type ( 'int', 'char', 'short', 'long', 'long long', 'float', 'double', 'long double', 'int *' ) {
    my $real_type = $type_map{$compiler}{$type} || $type;
    my $rv = $self->$meth( $real_type ) or next;
    $sizes{$type =~ y/*// ? 'pointer' : $type} = $rv;
  }

  my %enum;

  for my $type (
                 "enum pbyte { PB1 =      0, PB2 =   255 }",
                 "enum nbyte { NB1 =   -128, NB2 =   127 }",
                 "enum pword { PW1 =      0, PW2 = 65535 }",
                 "enum nword { NW1 = -32768, NW2 = 32767 }",
                 "enum plong { PL1 =      0, PL2 = 65536 }",
                 "enum nlong { NL1 = -32768, NL2 = 32768 }",
               ) {
    my $rv = $self->$meth( $type ) or next;
    my($name) = $type =~ /^enum\s+(\w+)/;
    $enum{$name} = $rv;
  }

  $self->_work_done;

  if( keys %enum == 6 ) {
    if( $enum{pbyte} == 2 && $enum{nbyte} == 1 &&
        $enum{pword} == 4 && $enum{nword} == 2 &&
        $enum{plong} == 4 && $enum{nlong} == 4 ) {
      $sizes{enum} = -1;
    }
    elsif( $enum{pbyte} == 1 && $enum{nbyte} == 1 &&
           $enum{pword} == 2 && $enum{nword} == 2 &&
           $enum{plong} == 4 && $enum{nlong} == 4 ) {
      $sizes{enum} = 0;
    }
    elsif( $enum{pbyte} == $enum{nbyte} &&
           $enum{pbyte} == $enum{pword} &&
           $enum{pbyte} == $enum{nword} &&
           $enum{pbyte} == $enum{plong} &&
           $enum{pbyte} == $enum{nlong} ) {
      $sizes{enum} = $enum{pbyte};
    }
    else {
      $self->_msg( "Hmm, your compiler has strange enums." );
    }
  }

  $self->_msg( "Got size information for the following types:" );
  $self->_wrapped_list( sort @{[map {y/ /_/; $_} keys %sizes]} );

  $self->_debug(sub { Data::Dumper->Dump( [\%sizes], ['*sizes'] ) });

  \%sizes;
}

#-----------------------------------------------------------------------
#  UNSIGNED CHARACTERS
#-----------------------------------------------------------------------

sub _get_unsigned_chars_run
{
  my $self = shift;

  $self->_temp( <<ENDC );
#include <stdio.h>
int main()
{
  char c;
  int  i;
  c = -1;
  i = c;
  printf("result=%d\\n", i);
}
ENDC

  my $res = $self->_build_temp;

  if( $res->{status} == 0 and -e $self->_exefile ) {
    {
      local $self->{fatal} = 0;
      $res = $self->_run_temp;
    }

    if( $res->{didnotrun} ) {
      $self->_msg( "It seems I cannot run your compiler executables." );
      return undef;
    }

    for my $line ( @{$res->{stdout}} ) {
      $line =~ /^result=(-?\d+)/ and return $1;
    }
  }
  else {
    $self->_msg( "Could not build the test program." );
    $self->_out( '| ', @{$res->{stderr}} );
  }

  return undef;
}

sub _get_unsigned_chars_compile
{
  my $self = shift;

  my $res = $self->_test_type( "int", "(int)((char)-1)", 8 );

  if( defined $res ) {
    $res =~ /^\xFF+$/        and return -1;
    $res =~ /^\x00+\xFF$/ ||
    $res =~ /^\xFF\x00+$/    and return 255;
  }

  $self->_msg( "Could not determine character signedness." );
  return undef;
}

sub _get_unsigned_chars
{
  my $self = shift;

  $self->_msg( "\nTrying to find out if your chars are unsigned..." );

  my $meth = $self->{can_run} ? "_get_unsigned_chars_run" : "_get_unsigned_chars_compile";

  my $result = $self->$meth();

  if( defined $result ) {
    if( $result == -1 ) {
      $self->_msg( "Your chars are signed." );
      return 0;
    }
    elsif( $result == 255 ) {
      $self->_msg( "Your chars are unsigned." );
      return 1;
    }
    elsif( $result >= 0 ) {
      $self->_msg( "Your chars seem to be unsigned." );
      return 1;
    }
    else {
      $self->_msg( "Your chars seem to be signed." );
      return 0;
    }
  }

  $self->_msg( "No idea." );
  return undef;
}

#-----------------------------------------------------------------------
#  BYTEORDER
#-----------------------------------------------------------------------

sub _get_byteorder_run
{
  my $self = shift;

  $self->_temp( <<ENDC );
#include <stdio.h>
typedef unsigned long UVAL;
typedef union {
  UVAL multi;
  char byte[sizeof(UVAL)];
} order;
int main()
{
  order test;
  int i;
  if( sizeof(UVAL) > 4 )
    test.multi = (((UVAL)0x08070605) << 32) | ((UVAL)0x04030201);
  else
    test.multi = (UVAL)0x04030201;
  printf("order=");
  for( i=0; i<sizeof(long); ++i )
    printf("\%c", '0'+test.byte[i]);
  printf("\\n");
  return 0;
}
ENDC

  my $res = $self->_build_temp;

  if( $res->{status} == 0 and -e $self->_exefile ) {
    {
      local $self->{fatal} = 0;
      $res = $self->_run_temp;
    }

    if( $res->{didnotrun} ) {
      $self->_msg( "It seems I cannot run your compiler executables." );
      return '';
    }

    my $order;

    for my $line ( @{$res->{stdout}} ) {
      $line =~ /^order=(\d+)/ and $order = $1;
    }

    if( defined $order ) {
      my %bo = (
        '87654321' => 'BigEndian',
        '4321'     => 'BigEndian',
        '21'       => 'BigEndian',
        '12345678' => 'LittleEndian',
        '1234'     => 'LittleEndian',
        '12'       => 'LittleEndian',
      );
      if( exists $bo{$order} ) {
        $self->_msg( "The byte order appears to be $bo{$order}." );
        return $bo{$order};
      }
      $self->_msg( "Your compiler seems to have a strange byte order ($order)." );
    }
    else {
      $self->_msg( "The test program delivered some strange output." );
      $self->_out( '| ', @{$res->{stdout}} );
    }
  }
  else {
    $self->_msg( "Could not build the test program." );
    $self->_out( '| ', @{$res->{stderr}} );
  }

  return '';
}

sub _get_byteorder_compile
{
  my $self = shift;

  my $res = $self->_test_type( "unsigned long", <<ENDINIT, 8 );
  sizeof(unsigned long) > 4
    ? (((unsigned long)0x08070605) << 32) | ((unsigned long)0x04030201)
    : (unsigned long)0x04030201
ENDINIT

  unless( defined $res ) {
    $self->_msg( "Could not determine byte order." );
    return '';
  }

  my %bo = (
    "\x08\x07\x06\x05\x04\x03\x02\x01" => 'BigEndian',
    "\x04\x03\x02\x01"                 => 'BigEndian',
    "\x02\x01"                         => 'BigEndian',
    "\x01\x02\x03\x04\x05\x06\x07\x08" => 'LittleEndian',
    "\x01\x02\x03\x04"                 => 'LittleEndian',
    "\x01\x02"                         => 'LittleEndian',
  );

  if( exists $bo{$res} ) {
    $self->_msg( "The byte order appears to be $bo{$res}." );
    return $bo{$res};
  }

  my $str = join '', map { sprintf "%02X", $_ } unpack "C*", $res;
  $self->_msg( "Your compiler seems to have a strange byte order (0x$str)." );

  return '';
}

sub _get_byteorder
{
  my $self = shift;

  $self->_msg( "\nTrying to determine byte order..." );

  my $meth = $self->{can_run} ? "_get_byteorder_run" : "_get_byteorder_compile";

  return $self->$meth();
}

#-----------------------------------------------------------------------
#  C++ COMMENTS
#-----------------------------------------------------------------------

sub _get_cpp_comments
{
  my $self = shift;

  $self->_msg( "\nTrying to find out if your compiler understands C++ comments..." );

  $self->_temp( <<ENDC );
extern int // nothing here
       i;
int main(void) { return 0; }  /* keep _build happy */
ENDC

  my $res = $self->_compile_or_build_temp;

  if( $res->{status} ) {
    $self->_msg( "No, it doesn't." );
    return 0;
  }
  else {
    $self->_msg( "Yes, it does." );
    return 1;
  }
}

#-----------------------------------------------------------------------
#  KEYWORD MAP
#-----------------------------------------------------------------------

sub _get_keyword_map
{
  my $self = shift;

  $self->_msg( "\nTrying to find out which special keywords your compiler knows..." );

  my @remap = qw( asm break case char continue default do else for goto if int return sizeof
                  struct switch typedef union while auto const double enum extern float
                  long register short signed static unsigned void volatile inline restrict );

  my @keywords = map { ("_${_}", "__${_}", "__${_}__") } sort
                 @remap, qw( bounded unbounded imag real complex extension );

  my @known;
  my $count = 0;

  for my $key ( sort @keywords ) {
    $self->_work_in_progress( sprintf "%d/%d keywords", scalar @known, $count++ );

    $self->_temp( <<ENDC );
typedef struct $key { int foo; } $key;
int main(void) { return 0; }  /* keep _build happy */
ENDC

    my $res = $self->_compile_or_build_temp;

    $res->{status} and push @known, $key;
  }

  $self->_work_done;

  if( @known ) {
    $self->_msg( "Your compiler recognizes the following special keywords:" );
    $self->_wrapped_list( sort @known );
  }
  else {
    $self->_msg( "None." );
  }

  $self->_debug(sub { Data::Dumper->Dump( [\@known], ['*known'] ) });

  my $remap = join '|', @remap;

  return { map { ( $_ => (/^_*($remap)_*$/ ? $1 : undef) ) } @known }
}

#-----------------------------------------------------------------------
#  INVALID KEYWORDS
#-----------------------------------------------------------------------

sub _get_invalid_keywords
{
  my $self = shift;

  $self->_msg( "\nTrying to find out which keywords your compiler doesn't know..." );


  my @keywords = qw( inline restrict auto const double enum extern float long
                     register short signed static unsigned void volatile asm );

  my @invalid;
  my $count = 0;

  for my $key ( sort @keywords ) {
    $self->_work_in_progress( sprintf "%d/%d keywords", scalar @invalid, $count++ );

    $self->_temp( <<ENDC );
typedef struct $key { int foo; } $key;
int main(void) { return 0; }  /* keep _build happy */
ENDC

    my $res = $self->_compile_or_build_temp;

    $res->{status} == 0 and push @invalid, $key;
  }

  $self->_work_done;

  if( @invalid ) {
    $self->_msg( "Your compiler doesn't recognize the following keywords:" );
    $self->_wrapped_list( sort @invalid );
  }
  else {
    $self->_msg( "Your compiler recognizes all keywords." );
  }

  $self->_debug(sub { Data::Dumper->Dump( [\@invalid], ['*invalid'] ) });

  \@invalid;
}

#-----------------------------------------------------------------------
#  PREDEFINED ASSERTIONS
#-----------------------------------------------------------------------

sub _get_preasserted
{
  my $self = shift;
  my $assert = shift;

  $self->_msg( "\nChecking for assertions (this may take a while)..." );

  my $code;

  for my $pred ( keys %$assert ) {
    for my $ans ( @{$assert->{$pred}} ) {
      $code .= <<ENDC;
#if #$pred($ans)
"$pred($ans)";
#endif
ENDC
    }
  }

  $self->_temp( $code );

  my $res = $self->_preprocess_temp;

  if( $res->{status} ) {
    $self->_msg( "Your compiler doesn't seem to like assertions." );
    return {};
  }

  my %results;

  for my $line ($self->_read_pp($res)) {
    chomp $line;
    next if $line =~ /^\s*#/;
    next if $line =~ /^\s*$/;
    $line =~ /"\s*([^"]+?)\s*"\s*;/ or next;
    $results{$1} = 1;
  }

  if( my $count = keys %results ) {
    my $what = $count > 1 ? "these $count assertions" : "this assertion";
    $self->_msg( "Your compiler makes $what:" );
    $self->_wrapped_list( sort keys %results );
  }
  else {
    $self->_msg( "Your compiler doesn't seem to assert anything." );
  }

  \%results;
}

#-----------------------------------------------------------------------
#  PREDEFINED MACROS
#-----------------------------------------------------------------------

sub _get_predefined
{
  my $self = shift;
  my $names = shift;
  my $pos = 0;

  my @stdnames = qw( __LINE__ __FILE__ __DATE__ __TIME__ __STDC__ _Pragma );

  $self->_msg( "\nChecking for predefined macros (this may take a while)..." );

  my %defs;

  for my $name ( &_preset_names ) {
    my @words = map { ("$_", "_$_", "__$_", "__${_}__" ) }
                    $name, uc($name), lc($name);
    @defs{@words} = (1)x@words;
  }

  my %results = ();
  my $count = 0;
  my $max = @$names;

  while(1) {
    delete @defs{@stdnames};

    $self->_work_in_progress( "($count) $pos/$max" );

    my $code;

    for my $def ( keys %defs ) {
      $code .= <<ENDC;
#ifdef $def
"$def";
($def);
#endif
ENDC
    }

    $self->_temp( $code );

    my $res = $self->_preprocess_temp;

    if( $res->{status} ) {
      $self->_work_done;
      $self->_msg( "Your compiler exited unexpectedly:" );
      $self->_out( '| ', @{$res->{stderr}} );
      return {};
    }

    my $out = join '', $self->_read_pp($res);

    while( $out =~ /"\s*([^\s"]+)\s*"\s*;\s*\(\s*([^\r\n]*?)\s*\)\s*;/g ) {
      $results{$1} = $2;
    }

    $count = keys %results;

    %defs = ();

    last if $pos >= @$names;

    my $last = $pos+999;
    $last = $#$names if $last > $#$names;
    @defs{@{$names}[$pos..$last]} = (1)x($last-$pos+1);
    $pos = $last+1;
  }

  delete @results{@stdnames};

  $self->_work_done;

  if( my $count = keys %results ) {
    my $what = $count > 1 ? "these $count symbols" : "this symbol";
    $self->_msg( "Your compiler defines $what:" );
    $self->_wrapped_list( sort keys %results );
  }
  else {
    $self->_msg( "Your compiler doesn't seem to define anything." );
  }

  $self->_debug(sub { Data::Dumper->Dump( [\%results], ['*results'] ) });

  \%results;
}

#-----------------------------------------------------------------------
#  INCLUDE PATH
#-----------------------------------------------------------------------

sub _incpath_main
{
  my($self, $quiet, @headers) = @_;
  my %resolve;

  for my $hdr ( @headers ) {
    $self->_work_in_progress;

    $self->_temp( <<TEMP );
#include <$hdr>
TEMP
    my $res = $self->_preprocess_temp;

    if( $res->{status} ) {
      $quiet or $self->_msg("Compiler choked on including '$hdr'. Maybe a missing ANSI header...");
      next;
    }

    for my $line ($self->_read_pp($res)) {
      if( $line =~ $self->{ppline} ) {
        my $file = $2;
        if( $file =~ /^(.*)\Q$hdr\E$/ ) {
          my $inc = $1;
          $inc =~ y{\\}{/}s;
          $resolve{$hdr} = [$inc];
          last;
        }
      }
    }
  }

  %resolve;
}

sub _get_files
{
  my($dir, $rex) = @_;
  local *DIR;

  opendir DIR, $dir or return ();
  my @files = readdir DIR;
  closedir DIR;

  if( defined $rex ) {
    return grep $_ =~ $rex, @files;
  }

  @files;
}

sub _run_incpath
{
  my $self = shift;
  my(@inc,@newhdr,%resolve);
  my @headers = @{$self->{headers}};

  $self->_msg( "\nTrying to determine include path..." );

  %resolve = $self->_incpath_main(0, @headers);
  @inc = _unique( map $_->[0], values %resolve );

  if( @inc > 1 ) {
    my @files;
    for my $path ( @inc ) {
      push @files, grep !-d $path.$_, _get_files( $path );
    }

    for my $hdr ( _unique( @files ) ) {
      my @f = grep { -e "$_$hdr" } @inc;
      @f > 1 && push @newhdr, $hdr;
    }

    push @headers, @newhdr;
    %resolve = ( %resolve, $self->_incpath_main(1, @newhdr) );

    for my $hdr ( @headers ) {
      for my $path ( @inc ) {
        next unless exists $resolve{$hdr};
        next if $path eq $resolve{$hdr}[0];
        -e $path.$hdr and push @{$resolve{$hdr}}, $path;
      }
    }

    $self->_debug(sub { Data::Dumper->Dump( [\%resolve], ['*resolve'] ) });

    my($i,$j);
    my @h = grep { @{$resolve{$_}} > 1 } keys %resolve;

    for( $i = 0; $i < @inc; ++$i ) {
      for( $j = $i+1; $j < @inc; ++$j ) {
        for my $h ( @h ) {
          my($a,$b) = @inc[$i,$j];
          my @r = @{$resolve{$h}};
          $b eq $r[0] or next;
          for( my $k = 1; $k < @r; ++$k ) {
            $r[$k] eq $a and @inc[$i,$j] = @inc[$j,$i];
          }
        }
      }
    }
  }

  $self->_work_done;

  $self->_debug(sub { Data::Dumper->Dump( [\@inc], ['*inc'] ) });

  $self->_msg( "The include path appears to be:" );
  $self->_msg( "  ($_) $inc[$_-1]" ) for 1 .. @inc;

  \@inc;
}

#-----------------------------------------------------------------------
#  GATHER MACRO / ASSERTION NAMES
#-----------------------------------------------------------------------

sub _names
{
  my $self = shift;
  my $inc_path = shift;
  my @ppkey = qw( define undef include line error pragma if ifdef ifndef defined elif else endif );
  my %files;
  my %names;
  my %asserts;

  $self->_msg( "\nSearching macro names and assertions..." );

  my @files = map { my $p = $_; map { $p.$_ } _get_files( $p, qr/\.[hH]$/ ) } @$inc_path;
  my $ff = 0;

  while( @files ) {
    my $file = shift @files;
    -e $file or next;
    exists $files{$file} and next;
    $files{$file} = 1;
    $ff = keys %files;
    $self->_work_in_progress( "$ff files found" );
    my $fh = new IO::File $file;
    next unless defined $fh;
    while( <$fh> ) {
      if( /^\s*#\s*include\s*[<"]([^>"]+)[>"]/ ) {
        for( '', @$inc_path ) {
          my $f = $_.$1;
          exists $files{$f} or push @files, $f;
        }
      }
    }
  }

  $self->_debug(sub { Data::Dumper->Dump([\%files], ['*files']) });

  $ff = keys %files;
  my $fs = 0;

  for my $name ( keys %files ) {
    my $count = keys %names;
    $fs++;
    $self->_work_in_progress( "($count) $fs/$ff files scanned" );
    -e $name or next;
    my $fh = new IO::File $name;
    next unless defined $fh;
    my $file = do { local $/; <$fh> };
    $file =~ s{\\\s*$/}{}g;
    while( $file =~ /\b([A-Za-z_]\w*)\b/g ) {
      $names{$1} ||= 1;
    }
    for my $line ( $file =~ /^\s*#(?:el)?if(.*)/gm ) {
      while( $line =~ /#\s*(\w+)\s*\(\s*(\w+)\s*\)/g ) {
        $asserts{$1}{$2} ||= 1;
      }
    }
  }

  delete @names{@ppkey};

  my @names = keys %names;

  my $assertions = 0;
  for( keys %asserts ) {
    $assertions += keys %{$asserts{$_}};
  }

  # merge assertions with fixed assertions from _assert()
  my $asserts = _assert();
  for my $q ( keys %$asserts ) {
    for my $a ( @{$asserts->{$q}} ) {
      $asserts{$q}{$a} ||= 1;
    }
  }

  for( keys %asserts ) {
    $asserts{$_} = [sort keys %{$asserts{$_}}];
  }

  $self->_work_done;
  $self->{debug} and $self->_debug(sub { Data::Dumper->Dump([\@names, \%asserts], [qw(*names *asserts)]) });

  $assertions = $assertions ? " and $assertions potential assertions" : '';
  $self->_msg( sprintf "Found %d potential macro names$assertions.", scalar @names );

  (\@names, \%asserts);
}

########################################################################
#
#  CONFIGURE
#
########################################################################

sub _configure
{
  my $self = shift;

  ### Purpose of _configure:
  ### Populate these options unless set by the user and
  ### check if they do what they're supposed to.
  ###
  ###   --cc             the C compiler
  ###   --preprocess     how to get preprocessor output from the compiler
  ###   --compile-obj    how to compile C file to object file
  ###   --compile-exe    how to compile C file to executable file
  ###
  ### TODO: detect a.out. (Probably glob <*> before and after running the compiler?)

  ### Save user values...

  my $user = {};

  for my $c (qw( cc preprocess compile-obj compile-exe )) {
    $user->{$c} = $self->{$c} if exists $self->{$c};
  }

  ### Let's go!

  $self->_cleanup_basename;
  $self->_msg("Checking if your compiler works...");

  ### First, try to find a working CC that we can run...

  my @CC = exists $user->{cc} ? ($user->{cc}) : (qw( cc gcc icc cl ));

  my $res;
  my $didnotrun;
  my $fullcc;

  do {
    my $ccname = shift @CC;
    $fullcc = which($ccname);
    $fullcc = $ccname if !defined $fullcc && -x $ccname;
    $didnotrun = 1;
    if (defined $fullcc) {
      $self->{cc} = $fullcc;
      $res = $self->_runprog($self->{cc});
      $didnotrun = $res->{didnotrun};
    }
    if ($didnotrun and exists $user->{cc}) {
      if (defined $fullcc) {
        $self->_msg("It seems your compiler '$self->{cc}' did not run.");
      }
      else {
        $self->_msg("I could not find your compiler '$self->{cc}'.");
      }
      $self->_quit;
    }
  } while ($didnotrun && @CC);

  if ($didnotrun) {
    $self->_msg("None of the compilers I know seemed to run.");
    $self->_msg("Try specifying a compiler using the --cc option.");
    $self->_quit;
  };

  $self->_msg("Found a working compiler at $self->{cc}\n");

  ### Ok, so we have a compiler. Let's see how to get preprocessor output...

  my $line = 'char*lotr="Very useful, no doubt, that was to Saruman; yet it seems that he was not content.";';

  $self->_temp(<<TEMP);
$line
TEMP

  my @PP  = exists $user->{preprocess} ? ($user->{preprocess}) : ('-E %c |', '-c -E %c |', '-sp %c');
  my @PPE = exists $user->{'pp-ext'}   ? ($user->{'pp-ext'})   : ('.i', '.p');

  my($have_source, $have_ppline, $pp_ext);

  do {
    $have_source = 0;
    $have_ppline = 0;

    $self->{preprocess} = shift @PP;

    $res = $self->_preprocess_temp;
    for my $ext (@PPE) {
      $self->{'pp-ext'} = $ext;
      if (-f $self->_ppfile) {
        $pp_ext = $ext;
        last;
      }
    }
    my @ppout = $self->_read_pp($res);

    for (@ppout) {
      /\Q$line/                                            and $have_source = 1;
      $_ =~ $self->{ppline} && $2 =~ /\Q$self->{basename}/ and $have_ppline = 1;
    }
  } while (!$have_source && @PP);

  $self->{'pp-ext'} = $pp_ext || '';
  $self->{can_preprocess} = $have_source;
  $self->{can_read_ppout} = $have_ppline;

  if (!$self->{can_preprocess}) {
    $self->_msg("I couldn't figure out how to get usable preprocessor output from the compiler.");
  }
  else {
    $self->_msg("I can get preprocessor output using rule [$self->{preprocess}].");
    $self->_msg("But I don't understand the preprocessor output.")
        unless $self->{can_read_ppout};
  }

  ### Compile/build executable files

  $self->{can_compile} = 0;
  $self->{can_build}   = 0;
  $self->{can_run}     = 0;

  $self->_cleanup_basename;
  $self->_temp( <<TEMP );
extern int i;
TEMP

  my @CCO = exists $user->{'compile-obj'} ? ($user->{'compile-obj'}) : ('-c -o %o %c', '%c');
  my @OBJ = exists $user->{'obj-ext'}     ? ($user->{'obj-ext'})     : @{_OS('obj-ext')};
  my $obj_ext;

  do {
    $self->{'compile-obj'} = shift @CCO;
    undef $obj_ext;
    for my $ext (@OBJ) {
      $self->{'obj-ext'} = $ext;
      $res = $self->_compile_temp;
      if (-f $self->_objfile) {
        $obj_ext = $ext;
        last;
      }
    }
    $self->{can_compile} = $res->{didnotrun} == 0 && $res->{status} == 0 && defined $obj_ext;
  } while (!$self->{can_compile} && @CCO);

  $self->{'obj-ext'} = $obj_ext || '';

  if ($self->{can_compile}) {
    $self->_msg("I can compile object files using rule [$self->{'compile-obj'}].");
  }
  else {
    $self->_msg("I cannot compile object files.");
  }

  if ($self->{run}) {
    $self->_cleanup_basename;
    $self->_temp(<<TEMP);
#include <stdio.h>
int main()
{
  printf("Hello World\\n");
  return 0;
}
TEMP

    my @CCE = exists $user->{'compile-exe'} ? ($user->{'compile-exe'}) : ('-o %e %c');
    my @EXE = exists $user->{'exe-ext'}     ? ($user->{'exe-ext'})     : @{_OS('exe-ext')};
    my $exe_ext;

    do {
      $self->{'compile-exe'} = shift @CCE;
      undef $exe_ext;
      for my $ext (@EXE) {
        $self->{'exe-ext'} = $ext;
        $res = $self->_build_temp;
        if (-f $self->_exefile) {
          $exe_ext = $ext;
          last;
        }
      }
      $self->{can_build} = $res->{didnotrun} == 0 && $res->{status} == 0 && defined $exe_ext;
    } while (!$self->{can_build} && @CCE);
  
    $self->{'exe-ext'} = $exe_ext || '';

    if ($self->{can_build}) {
      if ($self->{can_compile}) {
        $self->_msg("I can also build executable files using rule [$self->{'compile-exe'}].");
      }
      else {
        $self->_msg("But it seems I can build executable files using rule [$self->{'compile-exe'}].");
      }
      $res = $self->_run_temp;
  
      $self->{can_run} = $res->{didnotrun} == 0 && $res->{status} == 0
                         && grep /Hello World/, @{$res->{stdout}};
  
      if ($self->{can_run}) {
        $self->_msg("And I can run the executables. Great!");
      }
      else {
        $self->_msg("But I cannot run the executables. That should be fine, too.");
      }
    }
    else {
      if ($self->{can_compile}) {
        $self->_msg("But I cannot build executable files. No big deal.");
      }
      else {
        $self->_msg("And I cannot build executable files. Sigh.");
      }
    }
  }
  else {
    $self->_msg("No need to check if I can build executables.");
  }
  
  $self->_cleanup_basename;

  $self->_debug(sub { Data::Dumper->Dump( [$self], [qw(self)] ) });

  unless ($self->{can_preprocess} || $self->{can_compile} || $self->{can_run}) {
    my @opt = map { "--$_" } grep { !exists $user->{$_} }
              qw( preprocess compile-obj compile-exe );

    if (@opt) {
      my $last = pop @opt;
      my $opt = @opt ? join(', ', @opt) . " and $last options" : "$last option";
      $self->_msg_wrapped("\nTry using the $opt to specify compiler behaviour.");
    }

    $self->_quit;
  }
}

########################################################################
#
#  UTILITY ROUTINES
#
########################################################################

sub _OS
{
  my $prop = shift;
  my %os = (
    (map { ( $_ => {
      'obj-ext' => ['.obj', '.o'],
      'exe-ext' => ['.exe', ''],
      'file-sep' => '\\',
    } ) } qw( MSWin32 dos os2 ) ),
  );
  my %def = (
    'obj-ext' => ['.o', '.obj'],
    'exe-ext' => ['', '.exe'],
    'file-sep' => '/',
  );

  return exists $os{$^O} ? $os{$^O}{$prop} : $def{$prop};
}

sub _cleanup_basename
{
  my $self = shift;
  my %seen;
  my @basefiles = grep !$seen{$_}++, glob "$self->{basename}*";
  push @basefiles, grep !$seen{$_}++, glob "$self->{basename}.*";
  $self->_debug("cleaning up: @basefiles\n");
  unlink @basefiles;
}

sub _unique
{
  my %unique;
  grep !$unique{$_}++, @_;
}

sub _cfile
{
  my $self = shift;
  return $self->{basename} . ($self->{'c-ext'} || '');
}

sub _ppfile
{
  my $self = shift;
  return $self->{basename} . ($self->{'pp-ext'} || '');
}

sub _objfile
{
  my $self = shift;
  return $self->{basename} . ($self->{'obj-ext'} || '');
}

sub _exefile
{
  my $self = shift;
  return $self->{basename} . ($self->{'exe-ext'} || '');
}

sub _read_pp
{
  my($self, $res) = @_;

  if ($self->{preprocess} =~ /\|$/) {
    return @{$res->{stdout}};
  }

  my $f = new IO::File $self->_ppfile or return;

  return <$f>;
}

sub _temp
{
  my $self = shift;
  my $temp = $self->_cfile;
  $self->_debug( "creating temporary file '$temp'\n" );
  if (-e $temp) {
    unlink $temp
        or croak "Could not remove temporary file '$temp': $!\n";
  }
  my $f = new IO::File ">$temp"
      or croak "Could not open temporary file '$temp': $!\n";
  $f->print(@_);
}

sub _quit
{
  my $self = shift;
  $self->_msg("\nSorry, cannot continue.");
  $self->cleanup;
  exit(1);
}

sub _run_temp
{
  my $self = shift;
  $self->_runprog( "." . _OS('file-sep') . $self->_exefile );
}

sub _interpolate
{
  my($self, $template) = @_;
  my %replace = (
    c => $self->_cfile,
    o => $self->_objfile,
    e => $self->_exefile,
    i => $self->_ppfile,
  );
  my $match = join '|', keys %replace;
  $template =~ s/\s+\|$//;
  $template =~ s/%($match)/$replace{$1}/g;
  return shellwords($template);
}

sub _compile_or_build_temp
{
  my $self = shift;
  my $meth = $self->{can_compile} ? '_compile_temp' : '_build_temp';
  $self->$meth();
}

sub _build_temp
{
  my $self = shift;
  unlink $self->_exefile if -f $self->_exefile;  # make sure exe is removed
  $self->_runcc($self->_interpolate($self->{'compile-exe'}));
}

sub _compile_temp
{
  my $self = shift;
  unlink $self->_objfile if -f $self->_objfile;  # make sure obj is removed
  $self->_runcc($self->_interpolate($self->{'compile-obj'}));
}

sub _preprocess_temp
{
  my $self = shift;
  $self->_runcc($self->_interpolate($self->{'preprocess'}));
}

sub _runcc
{
  my $self = shift;
  $self->_runprog($self->{cc}, @{$self->{ccflags}}, @_);
}

sub _runprog
{
  my $self = shift;
  my $prog = shift;
  my @args = @_;

  eval { alarm 10; alarm 0; };
  my $has_alarm = $@ eq '';
  my $tmp = '_t_m_p_';

  $self->_debug( "running '$prog @args'\n" );

  eval {
    local $SIG{ALRM};

    if( $has_alarm ) {
      $SIG{ALRM} = sub { die "TIMEOUT\n" };
      alarm $self->{timeout};
    }

    my $run = $prog =~ m/\s/ ? qq("$prog") : $prog;

    system "$run @args >$tmp.out 2>$tmp.err";

    $has_alarm and alarm 0;
  };

  my %rval = (
    status => $? >> 8,
  );

  for my $p (qw(out err)) {
    my $file = "$tmp.$p";
    my @lines;
    if (-f $file) {
      {
        my $fh = IO::File->new($file);
        if (defined $fh) {
          @lines = <$fh>;
        }
      }
      unlink $file;
    }
    $rval{"std$p"} = \@lines;
  }

  $rval{didnotrun} = 0;

  if( @{$rval{stdout}} && $rval{stdout}[0] =~ /^Can't exec "\Q$prog\E":/ ) {
    $rval{didnotrun} = 1;
  }

  if( $^O eq 'MSWin32' && @{$rval{stdout}} == 0 && @{$rval{stderr}} == 0 && $rval{status} == 1 ) {
    $rval{didnotrun} = 1;
  }

  if( $rval{didnotrun} and $self->{fatal} ) {
    croak "could not run '$prog @args'\n";
  }

  $? & 128 and $rval{core}   = 1;
  $? & 127 and $rval{signal} = $? & 127;

  $self->{debug} and $self->_debug(sub { Data::Dumper->Dump( [\%rval], ['*rval'] ) });

  if( $self->{__int__} ) {
    $self->_msg( "\n\nInterrupted..." );
    $self->_quit;
  }

  \%rval;
}

sub _work_in_progress
{
  my $self = shift;
  $self->{quiet} and return;
  $self->{status} or return;
  my @prog = qw(
    ----------
    >---------
    *>--------
    +*>-------
    -+*>------
    --+*>-----
    ---+*>----
    ----+*>---
    -----+*>--
    ------+*>-
    -------+*>
    --------+*
    ---------+
    ----------
    ---------<
    --------<*
    -------<*+
    ------<*+-
    -----<*+--
    ----<*+---
    ---<*+----
    --<*+-----
    -<*+------
    <*+-------
    *+--------
    +---------
  );
  my $index = 0;
  my @t = times;
  my $t = $t[0]+$t[1]+$t[2]+$t[3];
  if( exists $self->{__progress__} ) {
    $t - $self->{__progress__} < 0.1 and return;
    $index = ++$self->{__prog_index__} % @prog;
  }
  print STDERR "\r", $prog[$index];
  if( @_ ) {
    my $str = ' ' . join( '', @_ );
    $str .= ' 'x(40-length($str));
    print STDERR $str;
  }
  if( $self->{__int__} ) {
    $self->_msg( "\n\nInterrupted..." );
    $self->_quit;
  }
  $self->{__progress__} = $t;
}

sub _work_done
{
  my $self = shift;
  $self->{quiet} and return;
  $self->{status} or return;
  delete $self->{__progress__};
  delete $self->{__prog_index__};
  print STDERR "\r", ' 'x50, "\r";
}

sub _msg
{
  my $self = shift;
  $self->{quiet} and return;
  if( $self->{debug} ) {
    my (undef,undef,$line,$sub) = caller 1;
    print STDERR "($sub:$line): ";
  }
  print STDERR @_, "\n";
}

sub _msg_wrapped
{
  my $self = shift;
  $self->{quiet} and return;
  my $string = '';
  if( $self->{debug} ) {
    my (undef,undef,$line,$sub) = caller 1;
    $string .= "($sub:$line): ";
  }
  $string .= join '', @_, "\n";
  print STDERR wrap('', '', $string);
}

sub _wrapped_list
{
  my $self = shift;
  $self->{quiet} and return;
  my $string = "[@_]\n";
  print STDERR wrap( '  ', '   ', $string );
}

sub _out
{
  my $self = shift;
  $self->{quiet} and return;
  my $pre = shift;
  my @args = @_;
  for( @args ) {
    s/^/$pre/gms;
    /[\r\n]+$/ or s/$/\n/;
  }
  print STDERR @args;
}

sub _debug
{
  my $self = shift;
  $self->{debug} or return;
  my @args = @_;
  my (undef,undef,$line,$sub) = caller 1;
  for (@args) {
    $_ = $_->() if ref $_ eq 'CODE';
    s/^/DEBUG | /gms;
  }
  print STDERR "DEBUG @ $sub:$line\n", @args;
}

sub which
{
  my $command = shift;
  my(@PATH, @PATHEXT, $cfg);

  my @config = (
    { os => 'MSWin32|dos|os2', path_sep => ';' , file_sep => '\\', var => 'PATH'     },
    { os => 'MacOS'          , path_sep => '\,', file_sep => ':' , var => 'Commands' },
    { os => '.*'             , path_sep => ':' , file_sep => '/' , var => 'PATH'     },
  );

  for( @config ) {
    if( $^O =~ /^(?:$_->{os})$/ ) {
      $cfg = $_;
      last;
    }
  }

  if( index( $command, $cfg->{file_sep} ) >= 0 ) {
    my $full;

    if( $^O eq 'MacOS' ) {
      -e $command and return $command;
    }
    else {
      -x $command and return $command;
      for my $ext ( @PATHEXT ) {
        -x "$command$ext" and return "$command$ext";
      }
    }
  }
  else {
    if( exists $ENV{$cfg->{var}} ) {
      my %uni;
      @PATH = grep !$uni{$_}++,
              split /$cfg->{path_sep}/, $ENV{$cfg->{var}};
    }

    if( exists $ENV{PATHEXT} ) {
      my %uni;
      @PATHEXT = grep !$uni{$_}++,
                 split /$cfg->{path_sep}/, $ENV{PATHEXT};
    }

    for my $dir ( @PATH ) {
      my $full;

      if( $^O eq 'MacOS' ) {
        $full = "$dir$command";
        -e $full and return $full;
      }
      else {
        $full = "$dir$cfg->{file_sep}$command";
        -x $full and return $full;
        for my $ext ( @PATHEXT ) {
          -x "$full$ext" and return "$full$ext";
        }
      }
    }
  }

  return undef;
}


__END__

=head1 NAME

ccconfig - Get Convert::Binary::C configuration for a compiler

=head1 SYNOPSIS

ccconfig I<options> [-- compiler-options]

I<options>:

  -c
  --cc             compiler   compiler executable to test
                              default: auto-determined
  
  -o
  --output-file    file       output filename
                              default: output to stdout

  -f
  --output-format  format     output format
                              default: dumper

  --basename       name       basename of the temporary test files
                              default: _t_e_s_t

  -I
  --inc-path       path       manually set compiler include path

  --preprocess     rule       compiler rule for preprocessing
  --compile-obj    rule       compiler rule for compiling objects
  --compile-exe    rule       compiler rule for compiling executables

  --c-ext          ext        extension of C source files
  --pp-ext         ext        extension of preprocessor output files
  --obj-ext        ext        extension of object files
  --exe-ext        ext        extension of executable files

  --nodelete                  don't delete temporary files
  --norun                     don't try to run executables
  --quiet                     don't display anything
  --nostatus                  don't display status indicator
  
  --version                   print version number
  
  --debug                     debug mode

Placeholders allowed in compiler rules:

  %c    C source file
  %o    object file
  %e    executable file
  %i    preprocessor output file
  |     result is written to stdout (only at end of rule)

=head1 DESCRIPTION

C<ccconfig> will try to determine a usable configuration for
Convert::Binary::C from testing a compiler executable. It is not
necessary that the binaries generated by the compiler can be
executed, so C<ccconfig> can also be used for cross-compilers.

This tool is still experimental, and you should neither rely
on its output without checking, nor expect it to work in your
environment.

=head1 OPTIONS

=head2 C<--cc> compiler

This option allows you to explicitly specify a compiler
executable. This is especially useful if you don't want
to use your system compiler. If this options is not given,
C<ccconfig> tries to guess a compiler.

=head2 C<--output-file> file

Write Convert::Binary::C configuration to the specified
file. The default is to write the configuration to C<stdout>.

=head2 C<--output-format> format

Specify the output format of the Convert::Binary::C configuration.
The following formats are currently supported:

  dumper      Output a %config hash using Data::Dumper
  require     Output in a format suitable for require

The default is C<dumper>.

=head2 C<--basename> name

Allows you to change the base name of the temporary test files.
This is used along with the various C<-ext> options to build
the filenames of C source files, preprocessor output files,
object files and executables.

=head2 C<--inc-path> path

This option allows you to manually set the include path of the
compiler. This is useful if C<ccconfig> cannot determine the
include path automatically, most probably because it cannot
parse the preprocessor output. This option can be specified
more than once.

=head2 C<--preprocess> rule

Using this option, you can specify a I<rule> that C<ccconfig>
uses to run the compiler to get preprocessor output. Most
compilers write the preprocessor output to standard output
when given the C<-E> option, i.e.

  cc -E foo.c

will preprocess F<foo.c> to standard output. The corresponding
rule for C<ccconfig> would be:

  ccconfig --preprocess='-E %c |'

The <%c> will be replaced with the C source filename, and the
pipe symbol signals that the result will be written to standard
output.

The following placeholders can be used in C<ccconfig> rules:

  %c    C source file
  %o    object file
  %e    executable file
  %i    preprocessor output file

Usually, C<ccconfig> tries to figure out the correct rules on
its own.

=head2 C<--compile-obj> rule

Like C<--preprocess>, this option allows you to define a rule
for how to compile an object file. For most compilers, this rule
will be something like

  ccconfig --compile-obj='-c -o %o %c'

=head2 C<--compile-exe> rule

Like C<--preprocess>, this option allows you to define a rule
for how to compile an executable file. For most compilers, this
rule will be something like

  ccconfig --compile-exe='-o %e %c'

Note that it is sufficient to specify either C<--compile-obj>
or C<--compile-exe>. So if your compiler can only create object
files, that's just fine.

=head2 C<--c-ext>

This option is used along with C<--basename> to build the name
of a C source file. This is usually set to C<.c>.
 
=head2 C<--pp-ext>

This option is used along with C<--basename> to build the name
of a preprocessor output file.
 
=head2 C<--obj-ext>

This option is used along with C<--basename> to build the name
of an object file.
 
=head2 C<--exe-ext>

This option is used along with C<--basename> to build the name
of an executable file.
 
=head2 C<--nodelete>

Don't attempt to delete temporary files that have been created
by the compiler. Normally, C<ccconfig> will look for all files
with the same basename as the temporary test file and delete
them.

=head2 C<--norun>

You can specify this option if the executables generated
by your compiler cannot be run on your machine, i.e. if
you have a cross-compiler. However, C<ccconfig> will
automatically find out that it cannot run the executables.

When this option is set, a different set of algorithms is
used to determine a couple of configuration settings. These
algorithms are all based upon placing a special signature
in the object file. They are less reliable that the standard
algorithms, so you shouldn't use them unless you have to.

=head2 C<--quiet>

Don't display anything except for the final configuration.

=head2 C<--nostatus>

Hide the status indicator. Recommended if you want to
redirect the script output to a file:

  ccconfig --nostatus >config.pl 2>ccconfig.log

=head2 C<--version>

Writes the program name, version and path to standard
output.

=head2 C<--debug>

Generate tons of debug output. Don't use unless you know
what you're doing.

=head1 EXAMPLES

Normally, a simple

  ccconfig

without arguments is enough if you want the configuration for
your system compiler. While C<ccconfig> is running, it will
write lots of status information to C<stderr>. When it's done,
it will usually dump a Perl hash table to C<stdout> which can
be directly used as a configuration for Convert::Binary::C.

If you want the configuration for a different compiler,
or C<ccconfig> cannot determine your system compiler
automatically, use

  ccconfig -c gcc32

if your compiler's name is C<gcc32>.

If you want to pass additional options to the compiler, you
can do so after a double-dash on the command line:

  ccconfig -- -g -DDEBUGGING

or

  ccconfig -c gcc32 -- -ansi -fshort-enums

If you'd like to interface with the Perl core, you may find
a suitable configuration using something like:

  ccconfig --cc=`perl -MConfig -e 'print $Config{cc}'` \
           -- `perl -MConfig -e 'print $Config{ccflags}'`

=head1 COPYRIGHT

Copyright (c) 2002-2011 Marcus Holland-Moritz. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

=head1 SEE ALSO

See L<Convert::Binary::C>.

=cut