From a8eab8b1402ceff505b0cdee440c02a72cc4307d Mon Sep 17 00:00:00 2001
From: Ulrich Drepper <drepper@redhat.com>
Date: Mon, 26 Oct 1998 17:59:59 +0000
Subject: Update.

	* include/libc-symbols.h: If HAVE_BUILTIN_EXPECT is not defined
	define __builtin_expect as a macro substituting to the first
	argument.
	* config.h.in: Define HAVE_BUILTIN_EXPECT.
	* configure.in: Add test for __builtin_expect.
---
 configure.in | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

(limited to 'configure.in')

diff --git a/configure.in b/configure.in
index d256af08da..40d9f55a16 100644
--- a/configure.in
+++ b/configure.in
@@ -987,6 +987,28 @@ static)
   ;;
 esac
 
+dnl Check whether compiler understands __builtin_expect.
+AC_CACHE_CHECK(for __builtin_expect, libc_cv_gcc_builtin_expect,
+[cat > conftest.c <<EOF
+#line __oline__ "configure"
+int foo (int a)
+{
+  a = __builtin_expect (a, 10);
+  return a == 10 ? 0 : 1;
+}
+EOF
+dnl No \ in command here because it ends up inside ''.
+if AC_TRY_COMMAND([${CC-cc} $CFLAGS -nostdlib -nostartfiles
+			    -o conftest conftest.c -lgcc >&AC_FD_CC]); then
+  libc_cv_gcc_builtin_expect=yes
+else
+  libc_cv_gcc_builtin_expect=no
+fi
+rm -f conftest*])
+if test "$libc_cv_gcc_builtin_expect" = yes; then
+  AC_DEFINE(HAVE_BUILTIN_EXPECT)
+fi
+
 ### End of automated tests.
 ### Now run sysdeps configure fragments.
 
-- 
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