gfortran -fopenmp is incompatible with -lacml_mp under at least some circumstances. The program is LAPACK Cholesky and its solver, converted to Fortran 90 and instrumented for a course. It fails with 4.4.1 in ACML (i.e. the LAPACK call returns an erroneous error value), and in 4.3.2 the solver (which does NOT call ACML) takes 10 times as long as it should do. Omitting the -fopenmp and using -lacml instead both work perfectly; i.e. it fails ONLY if both -fopenmp and -lacml_mp are used. Oh, and it works with -llapack, too. Oh, joy.
Here is some grobble: gosset$gfortran -v Using built-in specs. Target: x86_64-unknown-linux-gnu Configured with: ../configure --prefix=/home/nmm/gfortran --disable-shared --disable-threads --disable-bootstrap -enable-languages=fortran --enable-werror=yes --enable-checking=all --disable-decimal-float Thread model: single gcc version 4.4.1 (GCC) gosset$/usr/bin/gfortran -v Using built-in specs. Target: x86_64-suse-linux Configured with: ../configure --prefix=/usr --infodir=/usr/share/info --mandir=/usr/share/man --libdir=/usr/lib64 --libexecdir=/usr/lib64 --enable-languages=c,c++,objc,fortran,obj-c++,java,ada --enable-checking=release --with-gxx-include-dir=/usr/include/c++/4.3 --enable-ssp --disable-libssp --with-bugurl=http://bugs.opensuse.org/ --with-pkgversion='SUSE Linux' --disable-libgcj --disable-libmudflap --with-slibdir=/lib64 --with-system-zlib --enable-__cxa_atexit --enable-libstdcxx-allocator=new --disable-libstdcxx-pch --enable-version-specific-runtime-libs --program-suffix=-4.3 --enable-linux-futex --without-system-libunwind --with-cpu=generic --build=x86_64-suse-linux Thread model: posix gcc version 4.3.2 [gcc-4_3-branch revision 141291] (SUSE Linux) gfortran -Wall -std=f2003 -pedantic -O3 -fopenmp -o Cholesky_f \ Answers/Cholesky/one.f90 -lacml_mp ./Cholesky_one_f fred_f_1000 The source is fairly short and clean, but fred_f_1000 is 16 MB. The 4.4.1 failure shows with a 160 MB test file, but not the 4.3.2 one. Regards, Nick Maclaren, University of Cambridge Computing Service, New Museums Site, Pembroke Street, Cambridge CB2 3QH, England. Email: n...@cam.ac.uk Tel.: +44 1223 334761 Fax: +44 1223 334679 -- Summary: gfortran -fopenp and ACML_MP seem incompatible Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: nmm1 at cam dot ac dot uk http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41977
