--- c.m4.~1.171.~	2002-11-09 08:33:24.000000000 +1000
+++ c.m4	2002-11-09 08:37:44.000000000 +1000
@@ -165,6 +165,13 @@
 # Don't include <ctype.h> because on OSF/1 3.0 it includes
 # <sys/types.h> which includes <sys/select.h> which contains a
 # prototype for select.  Similarly for bzero.
+#
+# HP unbundled cc A.05.36 for ia64 under +O3 will optimize away "f=$1" if
+# it's the last thing in main, apparently on the basis that such an
+# assignment is unnecessary if the program is about to exit (a rash
+# assumption if some atexits are about to run).  Putting f=$1 in another
+# function prevents it getting removed and losing the link reference to $1.
+#
 m4_define([AC_LANG_FUNC_LINK_TRY(C)],
 [AC_LANG_PROGRAM(
 [/* System header to define __stub macros and hopefully few prototypes,
@@ -183,7 +190,11 @@
 }
 #endif
 ],
-[/* The GNU C library defines this for functions which it implements
+[}
+int
+conftest_$1()
+{
+/* The GNU C library defines this for functions which it implements
     to always fail with ENOSYS.  Some functions are actually named
     something starting with __ and the normal name is an alias.  */
 #if defined (__stub_$1) || defined (__stub___$1)