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-rw-r--r--REORG.TODO/sysdeps/i386/configure.ac52
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diff --git a/REORG.TODO/sysdeps/i386/configure.ac b/REORG.TODO/sysdeps/i386/configure.ac
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+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 "$config_machine" = i386; then
+  AC_MSG_ERROR([
+*** ERROR: Support for i386 is deprecated.
+*** Please use host i786, i686, i585 or i486.
+*** For example: /src/glibc/configure --host=i686-pc-linux-gnu ..."])
+fi
+
+# The GNU C Library can't be built for i386.  There are several reasons for
+# this restriction.  The primary reason is that i386 lacks the atomic
+# operations required to support the current NPTL implementation.  While it is
+# possible that such atomic operations could be emulated in the kernel to date
+# no such work has been done to enable this.  Even with NPTL disabled you still
+# have no atomic.h implementation.  Given the declining use of i386 we disable
+# support for building with `-march=i386' or `-mcpu=i386.' We don't explicitly
+# check for i386, instead we make sure the compiler has support for inlining
+# the builtin __sync_val_compare_and_swap. If it does then we should have no
+# problem building for i386.
+LIBC_COMPILER_BUILTIN_INLINED(
+  [__sync_val_compare_and_swap],
+  [int a, b, c; __sync_val_compare_and_swap (&a, b, c);],
+  [-O0],
+  [libc_cv_unsupported_i386=no],
+  [AC_MSG_ERROR([
+*** Building with -march=i386/-mcpu=i386 is not supported.
+*** Please use host i786, i686, i586, or i486.
+*** For example: /source/glibc/configure CFLAGS='-O2 -march=i686' ...])])
+
+dnl Check whether asm supports Intel MPX
+AC_CACHE_CHECK(for Intel MPX support, libc_cv_asm_mpx, [dnl
+cat > conftest.s <<\EOF
+        bndmov %bnd0,(%esp)
+EOF
+if AC_TRY_COMMAND(${CC-cc} -c $ASFLAGS conftest.s 1>&AS_MESSAGE_LOG_FD); then
+  libc_cv_asm_mpx=yes
+else
+  libc_cv_asm_mpx=no
+fi
+rm -f conftest*])
+if test $libc_cv_asm_mpx = yes; then
+  AC_DEFINE(HAVE_MPX_SUPPORT)
+fi
+
+AC_DEFINE(USE_REGPARMS)
+
+dnl It is always possible to access static and hidden symbols in an
+dnl position independent way.
+AC_DEFINE(PI_STATIC_AND_HIDDEN)