AC_CHECK_SIZEOF fails with minGW

[Werner LEMBERG]

[gcc-4.6.2-1-mingw32]
[binutils-2.22-1-mingw32]
[autoconf2.5-2.68-1-mingw32]

Folks,


I tried to build FreeType's current git with the latest minGW bundle
on a Windows 7 box, first calling its autogen.sh script, then
configuring it.  While doing this I got surprising messages on the
screen:

  ...
  checking size of int
  result: 0
  checking size of long
  result: 0
  ...

Looking into config.log, I see this:

======================================================================

configure:4188: checking size of int
configure:4193: gcc -o conftest.exe -g -O2   conftest.c  >&5
configure:4193: $? = 0
configure:4193: ./conftest.exe
./configure: line 1581: ./conftest.exe: No such file or directory
configure:4193: $? = 127
configure: program exited with status 127
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "FreeType"
| #define PACKAGE_TARNAME "freetype"
| #define PACKAGE_VERSION "2.4.8"
| #define PACKAGE_STRING "FreeType 2.4.8"
| #define PACKAGE_BUGREPORT "address@hidden"
| #define PACKAGE_URL ""
| #define HAVE_SYS_TYPES_H 1
| #define HAVE_SYS_STAT_H 1
| #define HAVE_STDLIB_H 1
| #define HAVE_STRING_H 1
| #define HAVE_MEMORY_H 1
| #define HAVE_STRINGS_H 1
| #define HAVE_INTTYPES_H 1
| #define HAVE_STDINT_H 1
| #define HAVE_UNISTD_H 1
| #define HAVE_FCNTL_H 1
| #define HAVE_UNISTD_H 1
| /* end confdefs.h.  */
| #include <stdio.h>
| #ifdef HAVE_SYS_TYPES_H
| # include <sys/types.h>
| #endif
| #ifdef HAVE_SYS_STAT_H
| # include <sys/stat.h>
| #endif
| #ifdef STDC_HEADERS
| # include <stdlib.h>
| # include <stddef.h>
| #else
| # ifdef HAVE_STDLIB_H
| #  include <stdlib.h>
| # endif
| #endif
| #ifdef HAVE_STRING_H
| # if !defined STDC_HEADERS && defined HAVE_MEMORY_H
| #  include <memory.h>
| # endif
| # include <string.h>
| #endif
| #ifdef HAVE_STRINGS_H
| # include <strings.h>
| #endif
| #ifdef HAVE_INTTYPES_H
| # include <inttypes.h>
| #endif
| #ifdef HAVE_STDINT_H
| # include <stdint.h>
| #endif
| #ifdef HAVE_UNISTD_H
| # include <unistd.h>
| #endif
| static long int longval () { return (long int) (sizeof (int)); }
| static unsigned long int ulongval () { return (long int) (sizeof (int)); }
| #include <stdio.h>
| #include <stdlib.h>
| int
| main ()
| {
| 
|   FILE *f = fopen ("conftest.val", "w");
|   if (! f)
|     return 1;
|   if (((long int) (sizeof (int))) < 0)
|     {
|       long int i = longval ();
|       if (i != ((long int) (sizeof (int))))
|       return 1;
|       fprintf (f, "%ld", i);
|     }
|   else
|     {
|       unsigned long int i = ulongval ();
|       if (i != ((long int) (sizeof (int))))
|       return 1;
|       fprintf (f, "%lu", i);
|     }
|   /* Do not output a trailing newline, as this causes \r\n confusion
|      on some platforms.  */
|   return ferror (f) || fclose (f) != 0;
| 
|   ;
|   return 0;
| }
configure:4207: result: 0

======================================================================

And indeed, manually compiling the above snippet with the given
compiler flags doesn't result in a binary!  If I remove the `-O2' flag it
works, and the created `conftest.val' contains `4'.

Is this a known issue?  It seems to me that -O2 optimizes a bit too
much...  


    Werner