I was, at Brice's request, trying out the hwloc-1.11.0 release on all sorts of x86 systems, with and without a patch for the inline asm for the cpuid instruction.
I came across the following UNRELATED error during "make check" on a (very old) Red Hat 8 system (that would be something like "Fedora negative-3"): make[3]: Entering directory `/home/pcp1/phargrov/OMPI/hwloc-1.11.0-linux-x86-RH8/BLD/tests/ports' CC libhwloc_port_aix_la-topology-aix.lo CCLD libhwloc-port-aix.la CC libhwloc_port_bgq_la-topology-bgq.lo topology-bgq.c: In function `hwloc_bgq_get_thread_cpubind': topology-bgq.c:115: `cpu_set_t' undeclared (first use in this function) topology-bgq.c:115: (Each undeclared identifier is reported only once topology-bgq.c:115: for each function it appears in.) topology-bgq.c:115: parse error before "bg_set" topology-bgq.c:122: `bg_set' undeclared (first use in this function) topology-bgq.c: In function `hwloc_bgq_set_thread_cpubind': topology-bgq.c:151: `cpu_set_t' undeclared (first use in this function) topology-bgq.c:151: parse error before "bg_set" topology-bgq.c:168: `bg_set' undeclared (first use in this function) make[3]: *** [libhwloc_port_bgq_la-topology-bgq.lo] Error 1 The following output from configure might be relevant: checking for sched_setaffinity... yes checking for sys/cpuset.h... no checking for cpuset_setaffinity... no checking for library containing pthread_getthrds_np... no checking for cpuset_setid... no -Paul -- Paul H. Hargrove phhargr...@lbl.gov Computer Languages & Systems Software (CLaSS) Group Computer Science Department Tel: +1-510-495-2352 Lawrence Berkeley National Laboratory Fax: +1-510-486-6900