Hi all, There is the following error when compiling mpich-3.0.1 with gcc-4.4.6 on x86_64 in the presence of valgrind-3.6.0. libtool: compile: gcc -DHAVE_CONFIG_H -I. -I./src/include -I./src/include -I./src/mpi/datatype -I./src/mpi/spawn -Isrc/util/logging/common -I./src/util/wrappers -I./src/util/wrappers -I./src/binding/cxx -I/home/cdaley/tmp_build/mpich3/mpich-3.0.1/src/binding/f77 -Isrc/binding/f90 -I./src/mpid/ch3/include -I./src/mpid/ch3/include -I./src/mpid/ch3/channels/nemesis/include -I./src/mpid/ch3/channels/nemesis/include -I./src/mpid/ch3/channels/nemesis/utils/monitor -I./src/mpid/common/datatype -I./src/mpid/common/datatype -I./src/mpid/common/sched -I./src/mpid/common/thread -I./src/pmi/simple -I/home/cdaley/tmp_build/mpich3/mpich-3.0.1/src/mpl/include -I/home/cdaley/tmp_build/mpich3/mpich-3.0.1/src/mpl/include -I/home/cdaley/tmp_build/mpich3/mpich-3.0.1/src/openpa/src -I/home/cdaley/tmp_build/mpich3/mpich-3.0.1/src/openpa/src -I/home/cdaley/tmp_build/mpich3/mpich-3.0.1/src/mpi/romio/include -g -O2 -MT src/mpi/comm/comm_create.lo -MD -MP -MF src/mpi/comm/.deps/comm_create.Tpo -c src/mpi/comm/comm_create.c -fPIC -DPIC -o src/mpi/comm/.libs/comm_create.o src/mpi/comm/comm_create.c: In function 'MPIR_Comm_create_calculate_mapping': src/mpi/comm/comm_create.c:163: error: expected ')' before ';' token src/mpi/comm/comm_create.c:164: error: expected ')' before ';' token comm_create.c:163: MPL_VG_CHECK_MEM_IS_DEFINED(*mapping_vcr_out, vcr_size * sizeof(**mapping_vcr_out)); expands to ((void)(__extension__({unsigned int _zzq_rlval; { volatile unsigned long long int _zzq_args[6]; volatile unsigned long long int _zzq_result; _zzq_args[0] = (unsigned long long int)(VG_USERREQ__CHECK_MEM_IS_DEFINED); _zzq_args[1] = (unsigned long long int)(((*mapping_vcr_out))); _zzq_args[2] = (unsigned long long int)(((vcr_size * sizeof(**mapping_vcr_out)))); _zzq_args[3] = (unsigned long long int)(0); _zzq_args[4] = (unsigned long long int)(0); _zzq_args[5] = (unsigned long long int)(0); __asm__ volatile("rolq $3, %%rdi ; rolq $13, %%rdi\n\t" "rolq $61, %%rdi ; rolq $51, %%rdi\n\t" "xchgq %%rbx,%%rbx" : "=d" (_zzq_result) : "a" (&_zzq_args[0]), "0" (0) : "cc", "memory" ); _zzq_rlval = _zzq_result; } _zzq_rlval; }));); Notice the ")););" at the end. The embedded ";" happens because mpl_valgrind.h:126: # define MPL_VG_CHECK_MEM_IS_DEFINED(addr_,len_) ((void)VALGRIND_CHECK_MEM_IS_DEFINED((addr_),(len_))) memcheck.h:169: [valgrind-3.6.0] #define VALGRIND_CHECK_MEM_IS_DEFINED(_qzz_addr,_qzz_len) \ VALGRIND_DO_CLIENT_REQUEST_EXPR(0, \ VG_USERREQ__CHECK_MEM_IS_DEFINED, \ (_qzz_addr), (_qzz_len), 0, 0, 0); This issue does not happen with newer versions of valgrind because the VALGRIND_CHECK_MEM_IS_DEFINED macro definition does not contain a semi-colon. memcheck.h:169: [valgrind-3.7.0] #define VALGRIND_CHECK_MEM_IS_DEFINED(_qzz_addr,_qzz_len) \ VALGRIND_DO_CLIENT_REQUEST_EXPR(0, \ VG_USERREQ__CHECK_MEM_IS_DEFINED, \ (_qzz_addr), (_qzz_len), 0, 0, 0) Reverse merging changeset 17240eb22c5455683e5544a9a4733fe4add6225c (previously r10453) http://trac.mpich.org/projects/mpich/changeset/17240eb22c5455683e5544a9a4733... allowed me to compile mpich-3.0.1 in the presence of valgrind-3.6.0. Hopefully this is helpful. Thanks, Chris