Bug 679491
| Summary: | OpenMP flags are disregarded by libtool in library link mode | ||||||
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| Product: | [Fedora] Fedora | Reporter: | Enrique <cquike> | ||||
| Component: | libtool | Assignee: | Karsten Hopp <karsten> | ||||
| Status: | CLOSED WONTFIX | QA Contact: | Fedora Extras Quality Assurance <extras-qa> | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | unspecified | ||||||
| Version: | 15 | CC: | karsten, rhbugs | ||||
| Target Milestone: | --- | ||||||
| Target Release: | --- | ||||||
| Hardware: | Unspecified | ||||||
| OS: | Unspecified | ||||||
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| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2012-08-07 16:43:26 UTC | Type: | --- | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
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I also reported it upstream, and it seems that there is already a patch: http://lists.gnu.org/archive/html/bug-libtool/2011-03/msg00022.html Could this patch enter in Fedora 15? Chao, Enrique Upstream patch witch complete signoff is at http://lists.gnu.org/archive/html/bug-libtool/2011-03/msg00024.html It is still present in Fedora 15. Version bumped This message is a notice that Fedora 15 is now at end of life. Fedora has stopped maintaining and issuing updates for Fedora 15. It is Fedora's policy to close all bug reports from releases that are no longer maintained. At this time, all open bugs with a Fedora 'version' of '15' have been closed as WONTFIX. (Please note: Our normal process is to give advanced warning of this occurring, but we forgot to do that. A thousand apologies.) Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, feel free to reopen this bug and simply change the 'version' to a later Fedora version. Bug Reporter: Thank you for reporting this issue and we are sorry that we were unable to fix it before Fedora 15 reached end of life. If you would still like to see this bug fixed and are able to reproduce it against a later version of Fedora, you are encouraged to click on "Clone This Bug" (top right of this page) and open it against that version of Fedora. Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Fedora release includes newer upstream software that fixes bugs or makes them obsolete. The process we are following is described here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping |
Created attachment 480191 [details] bug demo package Description of problem: I am trying to create an OpenMP library. I am using autotools+libtool to comile it. However, the -fopenmp is not properly handled by libtool, which leaves a library with missing symbols, due to the missing linked library libgomp (part of the OpenMP implementation). I have created a small package which shows the problem. The package creates a library called libompl which uses OpenMP constructions. I have used AC_OPENMP macro in configure.ac to get the flags used by OpenMP. I then pass those flags when linking the library (AM_LDFLAGS = $(OPENMP_CFLAGS)). One can see from the compilation that the proper flags are passed to libtool: /bin/sh ../libtool --tag=CC --mode=link gcc -fopenmp -g -O2 -fopenmp -o libompl.la -rpath /usr/local/lib omp_lib.lo -lm libtool: link: rm -fr .libs/libompl.a .libs/libompl.la .libs/libompl.lai .libs/libompl.so .libs/libompl.so.0 .libs/libompl.so.0.0.0 libtool: link: gcc -shared .libs/omp_lib.o -lm -Wl,-soname -Wl,libompl.so.0 -o .libs/libompl.so.0.0.0 However, the third line shows that libtool actual call has trimmed the -fopenmp option. This can be check asking the library for its dynamic dependencies: # ldd libompl/.libs/libompl.so linux-vdso.so.1 => (0x00007fffdffff000) libm.so.6 => /lib64/libm.so.6 (0x00007fac2853d000) libc.so.6 => /lib64/libc.so.6 (0x00007fac281be000) /lib64/ld-linux-x86-64.so.2 (0x00000038b9c00000) which misses libgomp.so The package also contains a small program that makes use of the library and fails at link time with these expected errors: libtool: link: gcc -g -O2 -o .libs/omp_test omp_test.o ../libompl/.libs/libompl.so -lm -Wl,-rpath -Wl,/usr/local/lib ../libompl/.libs/libompl.so: undefined reference to `GOMP_parallel_end' ../libompl/.libs/libompl.so: undefined reference to `omp_get_num_threads' ../libompl/.libs/libompl.so: undefined reference to `GOMP_barrier' ../libompl/.libs/libompl.so: undefined reference to `GOMP_parallel_start' ../libompl/.libs/libompl.so: undefined reference to `omp_get_thread_num' One might argue that the $(OPENMP_CFLAGS) should be added to the compilation of omp_test. However, the program does not use OpenMP directly, only trough libompl. In fact, as a "client" of the library, it doesn't have to know which other libraries are used by libgompl. As an example, the -lm dependency has been added automatically, even if not explicitly stated in the Makefile.am which compiles omp_test.c. How reproducible: Always. Steps to Reproduce: 1. # tar xvf omp_bug.tar 2. # cd omp_bug 3. # autoreconf -i -f -m 4. # ./configure 5. # make Actual results: Error messages: ../libompl/.libs/libompl.so: undefined reference to `GOMP_parallel_end' ../libompl/.libs/libompl.so: undefined reference to `omp_get_num_threads' ../libompl/.libs/libompl.so: undefined reference to `GOMP_barrier' ../libompl/.libs/libompl.so: undefined reference to `GOMP_parallel_start' ../libompl/.libs/libompl.so: undefined reference to `omp_get_thread_num' Expected results: Proper linking with libgomp.