diff options
Diffstat (limited to 'sysdeps/i386/configure.ac')
| -rw-r--r-- | sysdeps/i386/configure.ac | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/sysdeps/i386/configure.ac b/sysdeps/i386/configure.ac new file mode 100644 index 0000000000..96ab7b0f5a --- /dev/null +++ b/sysdeps/i386/configure.ac @@ -0,0 +1,93 @@ +GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory. +# Local configure fragment for sysdeps/i386. + +# We no longer support i386 since it lacks the atomic instructions +# required to implement NPTL threading. +if test "$config_machine" = i386; then + AC_MSG_ERROR([ +*** ERROR: Support for i386 is deprecated. +*** Please use host i786, i686, i585 or i486. +*** For example: /src/glibc/configure --host=i686-pc-linux-gnu ..."]) +fi + +# The GNU C Library can't be built for i386. There are several reasons for +# this restriction. The primary reason is that i386 lacks the atomic +# operations required to support the current NPTL implementation. While it is +# possible that such atomic operations could be emulated in the kernel to date +# no such work has been done to enable this. Even with NPTL disabled you still +# have no atomic.h implementation. Given the declining use of i386 we disable +# support for building with `-march=i386' or `-mcpu=i386.' We don't explicitly +# check for i386, instead we make sure the compiler has support for inlining +# the builtin __sync_val_compare_and_swap. If it does then we should have no +# problem building for i386. +LIBC_COMPILER_BUILTIN_INLINED( + [__sync_val_compare_and_swap], + [int a, b, c; __sync_val_compare_and_swap (&a, b, c);], + [-O0], + [libc_cv_unsupported_i386=no], + [AC_MSG_ERROR([ +*** Building with -march=i386/-mcpu=i386 is not supported. +*** Please use host i786, i686, i586, or i486. +*** For example: /source/glibc/configure CFLAGS='-O2 -march=i686' ...])]) + +AC_CHECK_HEADER([cpuid.h], , + [AC_MSG_ERROR([gcc must provide the <cpuid.h> header])], + [/* No default includes. */]) + +dnl Check if -msse4 works. +AC_CACHE_CHECK(for SSE4 support, libc_cv_cc_sse4, [dnl +LIBC_TRY_CC_OPTION([-msse4], [libc_cv_cc_sse4=yes], [libc_cv_cc_sse4=no]) +]) +if test $libc_cv_cc_sse4 = yes; then + AC_DEFINE(HAVE_SSE4_SUPPORT) +fi +LIBC_CONFIG_VAR([config-cflags-sse4], [$libc_cv_cc_sse4]) + +dnl Check if -Wa,-mtune=i686 works. +AC_CACHE_CHECK(for assembler -mtune=i686 support, libc_cv_as_i686, [dnl +LIBC_TRY_CC_OPTION([-Wa,-mtune=i686], + [libc_cv_as_i686=yes], + [libc_cv_as_i686=no]) +]) +LIBC_CONFIG_VAR([config-asflags-i686], [$libc_cv_as_i686]) + +dnl Check if -mavx works. +AC_CACHE_CHECK(for AVX support, libc_cv_cc_avx, [dnl +LIBC_TRY_CC_OPTION([-mavx], [libc_cv_cc_avx=yes], [libc_cv_cc_avx=no]) +]) +if test $libc_cv_cc_avx = yes; then + AC_DEFINE(HAVE_AVX_SUPPORT) +fi +LIBC_CONFIG_VAR([config-cflags-avx], [$libc_cv_cc_avx]) + +dnl Check if -msse2avx works. +AC_CACHE_CHECK(for AVX encoding of SSE instructions, libc_cv_cc_sse2avx, [dnl +LIBC_TRY_CC_OPTION([-msse2avx], + [libc_cv_cc_sse2avx=yes], + [libc_cv_cc_sse2avx=no]) +]) +if test $libc_cv_cc_sse2avx = yes; then + AC_DEFINE(HAVE_SSE2AVX_SUPPORT) +fi +LIBC_CONFIG_VAR([config-cflags-sse2avx], [$libc_cv_cc_sse2avx]) + +dnl Check if -mfma4 works. +AC_CACHE_CHECK(for FMA4 support, libc_cv_cc_fma4, [dnl +LIBC_TRY_CC_OPTION([-mfma4], [libc_cv_cc_fma4=yes], [libc_cv_cc_fma4=no]) +]) +if test $libc_cv_cc_fma4 = yes; then + AC_DEFINE(HAVE_FMA4_SUPPORT) +fi +LIBC_CONFIG_VAR([have-mfma4], [$libc_cv_cc_fma4]) + +dnl Check if -mno-vzeroupper works. +AC_CACHE_CHECK(for -mno-vzeroupper support, libc_cv_cc_novzeroupper, [dnl +LIBC_TRY_CC_OPTION([-mno-vzeroupper], + [libc_cv_cc_novzeroupper=yes], + [libc_cv_cc_novzeroupper=no]) +]) +LIBC_CONFIG_VAR([config-cflags-novzeroupper], [$libc_cv_cc_novzeroupper]) + +dnl It is always possible to access static and hidden symbols in an +dnl position independent way. +AC_DEFINE(PI_STATIC_AND_HIDDEN) |