Wow, its a feature, not a bug. Its strange that it works without the
-xassembler when using gcc 4.2.
-Nathan
HPC-3, LANL
On Tue, 25 Jan 2011, Paul H. Hargrove wrote:
I found a root cause and a simpler/better simple fix:
From manpage for gcc on Linux:
file.s
Assembler code.
And from Darwin:
file.s
Assembler code. Apple's version of GCC runs the preprocessor
on these files as well as
those ending in .S.
So the problem/difference is that Apple insists on passing the .s through the
preprocessor by default when FSF's gcc does not.
The fix appears to be an explict "-xassembler":
$ cat foo.s
.text
# _gsym_test_func
.globl _gsym_test_func
_gsym_test_func:
# _gsym_test_func
$ gcc -std=c99 -c foo.s
foo.s:2:3: error: invalid preprocessing directive #_gsym_test_func
foo.s:5:3: error: invalid preprocessing directive #_gsym_test_func
$ gcc -std=c99 -c -xassembler foo.s
[no output]
-Paul
On 1/25/2011 2:48 PM, Nathan Hjelm wrote:
Ok, then there are two possible simple fixes:
- Strip -std from CCASFLAGS if Apple's gcc 4.0 is encountered, or
- Always strip -std from CCASFLAGS. The flag shouln't have any effect
when compiling assembly.
-Nathan
HPC-3, LANL
On Tue, 25 Jan 2011, Paul H. Hargrove wrote:
I can confirm that the problem appears specific to Apple's compiler.
Since the failure was reported to be configure-time, that took less
time to check up on that I'd
expected.
What I find is that gcc-4.0.0 on Linux/x86 *does* fail the
"#_gsym_test_func" test, but for the RIGHT
reason, and then goes on to
pass the next test case with the proper form of global symbol. The
relevent portion of config.log
appears below.
-Paul
configure:27399: checking prefix for global symbol labels
configure: trying _
configure:27439: gcc -std=gnu99 -O3 -DNDEBUG -finline-functions
-fno-strict-aliasing -c conftest.s
>conftest.out 2>&1
configure:27442: $? = 0
configure:27447: gcc -std=gnu99 -O3 -DNDEBUG -finline-functions
-fno-strict-aliasing -I. conftest_c.c -c
> conftest.cmpl 2>&1
configure:27450: $? = 0
configure:27455: gcc -std=gnu99 -O3 -DNDEBUG -finline-functions
-fno-strict-aliasing conftest_c.o
conftest.o -o conftest >
conftest.link 2>&1
configure:27458: $? = 1
conftest_c.o: In function `main':
conftest_c.o(.text+0xd): undefined reference to `gsym_test_func'
collect2: ld returned 1 exit status
configure: failed C program was:
#ifdef __cplusplus
extern "C" {
#endif
void gsym_test_func(void);
#ifdef __cplusplus
}
#endif
int
main()
{
gsym_test_func();
return 0;
}
configure: failed ASM program was:
.text
# _gsym_test_func
.globl _gsym_test_func
_gsym_test_func:
# _gsym_test_func
configure: trying
configure:27439: gcc -std=gnu99 -O3 -DNDEBUG -finline-functions
-fno-strict-aliasing -c conftest.s
>conftest.out 2>&1
configure:27442: $? = 0
configure:27447: gcc -std=gnu99 -O3 -DNDEBUG -finline-functions
-fno-strict-aliasing -I. conftest_c.c -c
> conftest.cmpl 2>&1
configure:27450: $? = 0
configure:27455: gcc -std=gnu99 -O3 -DNDEBUG -finline-functions
-fno-strict-aliasing conftest_c.o
conftest.o -o conftest >
conftest.link 2>&1
configure:27458: $? = 0
configure:27496: result:
On 1/25/2011 2:19 PM, Paul H. Hargrove wrote:
I have gcc-4.0.0 on Linux built from unmodified FSF sources.
I will try to reproduce.
-Paul
On 1/25/2011 1:47 PM, Nathan Hjelm wrote:
Looks like a bug in Apple's gcc 4.0. I tried the source
with gcc 3.4.6 and gcc 4.1.2 on Linux
and did not
see that error.
I will take a look and see if there is a simple fix to
get around this apparent compiler bug.
-Nathan
On Tue, 25 Jan 2011, Jeff Squyres wrote:
Short version
=============
MTT turned up a problem with -std=gnu99 on OS X
Leopard, which ships with the gcc 4.0
compiler (OS X Snow Leopard ships with gcc 4.2,
and doesn't have a problem). Does
anyone
have gcc 4.0 on Linux? I'm wondering if the same
problem would occur.
More details:
=============
From our friends at Absoft:
-----
The -std=gnu99 is causing the problem when used
with gcc-4.0 ( the default on Leopard
with
Apple's XCode 3.1 development tools ):
BigMac:ompi cag$ gcc --version -std=gnu99 -c
conftest.s
conftest.s:2:3: error: invalid preprocessing
directive #_gsym_test_func
conftest.s:5:3: error: invalid preprocessing
directive #_gsym_test_func
BigMac:ompi cag$ gcc-4.0 -std=gnu99 -c conftest.s
conftest.s:2:3: error: invalid preprocessing
directive #_gsym_test_func
conftest.s:5:3: error: invalid preprocessing
directive #_gsym_test_func
BigMac:ompi cag$ gcc-4.2 -std=gnu99 -c conftest.s
BigMac:ompi cag$
On Snow Leopard with Apple's XCode 3.2
development tools, the default compiler is 4.2.
-----
The compile line he's talking about in particular
is from a configure test in
opal/config/opal_config_asm.m4, where we're
looking for assembly global symbols. The
source
that we're trying to compile is:
-----
.text
# _gsym_test_func
.globl _gsym_test_func
_gsym_test_func:
# _gsym_test_func
-----
(configure tries a few prefixes)
But the "#" token with the -std=gnu99 option is
causing failures where it shouldn't
(i.e., it
causes configure to abort because all the
assembly tests looking for the global symbols
error
out due to the # token.
So I think we either need to find a workaround
for this assembly test or whack the idea
of
the C99 stuff. :-(
On Jan 24, 2011, at 10:29 AM, Nathan Hjelm wrote:
No, they didn't get added (adding them
now). I didn't get a chance to add them
over the weekend.
-Nathan
On Mon, 24 Jan 2011, Jeff Squyres wrote:
I'm getting these:
CC dummy_component.lo
dummy_component.c:25: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:28: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:29: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:30: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:31: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:33: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:34: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:35: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:37: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c:39: warning: ISO
C90 forbids specifying subobject
to initialize
dummy_component.c: In function
‘component_open’:
dummy_component.c:45: warning: unused
variable ‘c’
dummy.c:67: warning: ISO C90 forbids
specifying subobject to
initialize
dummy.c:68: warning: ISO C90 forbids
specifying subobject to
initialize
dummy.c:69: warning: ISO C90 forbids
specifying subobject to
initialize
dummy.c:70: warning: ISO C90 forbids
specifying subobject to
initialize
CCLD mca_debugger_dummy.la
Did the autoconf tests not get added?
--
Jeff Squyres
[email protected]
For corporate legal information go to:
http://www.cisco.com/web/about/doing_business/legal/cri/
_______________________________________________
devel mailing list
[email protected]
http://www.open-mpi.org/mailman/listinfo.cgi/devel
_______________________________________________
devel mailing list
[email protected]
http://www.open-mpi.org/mailman/listinfo.cgi/devel
--
Jeff Squyres
[email protected]
For corporate legal information go to:
http://www.cisco.com/web/about/doing_business/legal/cri/
_______________________________________________
devel mailing list
[email protected]
http://www.open-mpi.org/mailman/listinfo.cgi/devel
_______________________________________________
devel mailing list
[email protected]
http://www.open-mpi.org/mailman/listinfo.cgi/devel
--
Paul H. Hargrove [email protected]
Future Technologies Group
HPC Research Department Tel: +1-510-495-2352
Lawrence Berkeley National Laboratory Fax: +1-510-486-6900
_______________________________________________
devel mailing list
[email protected]
http://www.open-mpi.org/mailman/listinfo.cgi/devel
--
Paul H. Hargrove [email protected]
Future Technologies Group
HPC Research Department Tel: +1-510-495-2352
Lawrence Berkeley National Laboratory Fax: +1-510-486-6900
_______________________________________________
devel mailing list
[email protected]
http://www.open-mpi.org/mailman/listinfo.cgi/devel
--
Paul H. Hargrove [email protected]
Future Technologies Group
HPC Research Department Tel: +1-510-495-2352
Lawrence Berkeley National Laboratory Fax: +1-510-486-6900
