Re: Forcing -fno-strict-aliasing to all compiles breaks compiles with xlc/xlc_r

No joy.

xlc -fno-strict-aliasing -c -o conftest.o confest.c
will work
Follow that with
xlc -fno-strict-aliasing -c -o conftest conftest.o
and it'll error with 
ld: 0706-005 Cannot find or open file: no-strict-aliasing
        ld:fopen(): A file or directory in the path name does not exist.
This is because '-f' supposed to be passed to 'ld' by xlc on AIX.

Your test is including the '-c', allowing it to pass.

I think the root problem is being introduced with placing $CFLAGS in the 
link invocation of libtool.
Unfortunately, this solution would lead to other problems if someone is 
also making use of '-qipa' in optimization (Not that it makes much sense 
for this package).

Thanks,
Chris Dukes




Bojan Smojver <[email protected]> 
03/02/2008 05:32 PM

To
Chris Dukes/Durham/Contr/IBM@IBMUS
cc
[email protected]
Subject
Re: Forcing -fno-strict-aliasing to all compiles breaks compiles with 
xlc/xlc_r






On Mon, 2008-03-03 at 09:03 +1100, Bojan Smojver wrote:

> Yeah, we should only use -fno-strict-aliasing with GCC.

Can you let me know if this helps? You'll need to run buildconf, of
course...

-- 
Bojan

Index: acinclude.m4
===================================================================
--- acinclude.m4	(revision 632858)
+++ acinclude.m4	(working copy)
@@ -214,8 +214,13 @@
                       ])
                 # -Wdeclaration-after-statement is only supported on gcc 3.4+
         fi
-        APR_ADDTO([CFLAGS], "-fno-strict-aliasing")
 
+        old_cflags="$CFLAGS"
+        CFLAGS="$CFLAGS -fno-strict-aliasing"
+        AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]])],
+                          [CFLAGS=$old_cflags; APR_ADDTO([CFLAGS], "-fno-strict-aliasing")],
+                          [CFLAGS=$old_cflags])
+
         APR_ADDTO([CPPFLAGS], "`$APR_CONFIG --cppflags`")
 
         get_version="$SHELL $abs_srcdir/build/get-version.sh"