From aec1eb30482afb97764e3abda8dd7d7749d4f597 Mon Sep 17 00:00:00 2001
From: Gary Houston <ghouston@arglist.com>
Date: Fri, 18 Aug 2000 22:44:12 +0000
Subject: [PATCH] 	* acconfig.h: added BROKEN_GCSE. 	*
 configure.in: check for a gcc GCSE optimisation bug.

---
 acconfig.h   |  3 +++
 configure.in | 27 +++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/acconfig.h b/acconfig.h
index b7b42bc3d..cf5e0fff2 100644
--- a/acconfig.h
+++ b/acconfig.h
@@ -154,3 +154,6 @@
 
 /* Define if the compiler supports long longs.  */
 #undef HAVE_LONG_LONGS
+
+/* Define if GCC has GCSE optimisation bug.  */
+#undef BROKEN_GCSE
diff --git a/configure.in b/configure.in
index 09e897dee..3c4126e90 100644
--- a/configure.in
+++ b/configure.in
@@ -129,6 +129,33 @@ if test "$scm_cv_long_longs" = yes; then
   AC_DEFINE(HAVE_LONG_LONGS)
 fi
 
+dnl check for an optimisation problem which is present in some versions
+dnl of gcc, including 2.95.2.
+AC_MSG_CHECKING(for broken GCSE optimisation)
+AC_CACHE_VAL(guile_cv_broken_gcse,
+   AC_TRY_RUN([
+	int main ()
+	{
+	  long winds = 0;
+
+	  while (winds != 0)
+	    {
+	      if (*(char *) 0)
+	        break;
+	    }
+
+	  if (winds == 0 || *(char *) 0)
+	    exit (0);
+
+	  return 0;
+	}],
+        guile_cv_broken_gcse=no, guile_cv_broken_gcse=yes,
+        guile_cv_broken_gcse=yes))
+AC_MSG_RESULT($guile_cv_broken_gcse)
+if test $guile_cv_broken_gcse = yes; then
+   AC_DEFINE(BROKEN_GCSE)
+fi
+
 AC_HEADER_STDC
 AC_HEADER_DIRENT
 AC_HEADER_TIME