| | 1 | dnl @synopsis AC_C_BIGENDIAN_CROSS |
| | 2 | dnl |
| | 3 | dnl Check endianess even when crosscompiling |
| | 4 | dnl (partially based on the original AC_C_BIGENDIAN). |
| | 5 | dnl |
| | 6 | dnl The implementation will create a binary, and instead of running |
| | 7 | dnl the binary it will be grep'ed for some symbols that will look |
| | 8 | dnl different for different endianess of the binary. |
| | 9 | dnl |
| | 10 | dnl @author Guido Draheim <guidod@gmx.de> |
| | 11 | dnl |
| | 12 | AC_DEFUN([AC_C_BIGENDIAN_CROSS], |
| | 13 | [AC_CACHE_CHECK(whether byte ordering is bigendian, ac_cv_c_bigendian, |
| | 14 | [ac_cv_c_bigendian=unknown |
| | 15 | # See if sys/param.h defines the BYTE_ORDER macro. |
| | 16 | AC_TRY_COMPILE([#include <sys/types.h> |
| | 17 | #include <sys/param.h>], [ |
| | 18 | #if !BYTE_ORDER || !BIG_ENDIAN || !LITTLE_ENDIAN |
| | 19 | bogus endian macros |
| | 20 | #endif], [# It does; now see whether it defined to BIG_ENDIAN or not. |
| | 21 | AC_TRY_COMPILE([#include <sys/types.h> |
| | 22 | #include <sys/param.h>], [ |
| | 23 | #if BYTE_ORDER != BIG_ENDIAN |
| | 24 | not big endian |
| | 25 | #endif], ac_cv_c_bigendian=yes, ac_cv_c_bigendian=no)]) |
| | 26 | if test $ac_cv_c_bigendian = unknown; then |
| | 27 | AC_TRY_RUN([main () { |
| | 28 | /* Are we little or big endian? From Harbison&Steele. */ |
| | 29 | union |
| | 30 | { |
| | 31 | long l; |
| | 32 | char c[sizeof (long)]; |
| | 33 | } u; |
| | 34 | u.l = 1; |
| | 35 | exit (u.c[sizeof (long) - 1] == 1); |
| | 36 | }], ac_cv_c_bigendian=no, ac_cv_c_bigendian=yes, |
| | 37 | [ echo $ac_n "cross-compiling... " 2>&AC_FD_MSG ]) |
| | 38 | fi]) |
| | 39 | if test $ac_cv_c_bigendian = unknown; then |
| | 40 | AC_MSG_CHECKING(to probe for byte ordering) |
| | 41 | [ |
| | 42 | cat >conftest.c <<EOF |
| | 43 | short ascii_mm[] = { 0x4249, 0x4765, 0x6E44, 0x6961, 0x6E53, 0x7953, 0 }; |
| | 44 | short ascii_ii[] = { 0x694C, 0x5454, 0x656C, 0x6E45, 0x6944, 0x6E61, 0 }; |
| | 45 | void _ascii() { char* s = (char*) ascii_mm; s = (char*) ascii_ii; } |
| | 46 | short ebcdic_ii[] = { 0x89D3, 0xE3E3, 0x8593, 0x95C5, 0x89C4, 0x9581, 0 }; |
| | 47 | short ebcdic_mm[] = { 0xC2C9, 0xC785, 0x95C4, 0x8981, 0x95E2, 0xA8E2, 0 }; |
| | 48 | void _ebcdic() { char* s = (char*) ebcdic_mm; s = (char*) ebcdic_ii; } |
| | 49 | int main() { _ascii (); _ebcdic (); return 0; } |
| | 50 | EOF |
| | 51 | ] if test -f conftest.c ; then |
| | 52 | if ${CC-cc} -c conftest.c -o conftest.o && test -f conftest.o ; then |
| | 53 | if test `grep -l BIGenDianSyS conftest.o` ; then |
| | 54 | echo $ac_n ' big endian probe OK, ' 1>&AC_FD_MSG |
| | 55 | ac_cv_c_bigendian=yes |
| | 56 | fi |
| | 57 | if test `grep -l LiTTleEnDian conftest.o` ; then |
| | 58 | echo $ac_n ' little endian probe OK, ' 1>&AC_FD_MSG |
| | 59 | if test $ac_cv_c_bigendian = yes ; then |
| | 60 | ac_cv_c_bigendian=unknown; |
| | 61 | else |
| | 62 | ac_cv_c_bigendian=no |
| | 63 | fi |
| | 64 | fi |
| | 65 | echo $ac_n 'guessing bigendian ... ' >&AC_FD_MSG |
| | 66 | fi |
| | 67 | fi |
| | 68 | AC_MSG_RESULT($ac_cv_c_bigendian) |
| | 69 | fi |
| | 70 | if test $ac_cv_c_bigendian = yes; then |
| | 71 | AC_DEFINE(WORDS_BIGENDIAN, 1, [whether byteorder is bigendian]) |
| | 72 | BYTEORDER=4321 |
| | 73 | else |
| | 74 | BYTEORDER=1234 |
| | 75 | fi |
| | 76 | AC_DEFINE_UNQUOTED(BYTEORDER, $BYTEORDER, [1234 = LIL_ENDIAN, 4321 = BIGENDIAN]) |
| | 77 | if test $ac_cv_c_bigendian = unknown; then |
| | 78 | AC_MSG_ERROR(unknown endianess - sorry, please pre-set ac_cv_c_bigendian) |
| | 79 | fi |
| | 80 | ]) |
projects / wxWidgets.git / blame_incremental