For debugging purporse, we can disable the hwloc lib with the --without-hwloc

configure.ac

@@ -977,12 +977,16 @@ PKG_CHECK_MODULES([FFTWL], [fftw3l], [
 ], [:])
 AM_CONDITIONAL(STARPU_HAVE_FFTWL, [test x$have_fftwl = xyes])
 
-PKG_CHECK_MODULES([HWLOC], [hwloc], [
-  AC_DEFINE([STARPU_HAVE_HWLOC], [1], [Define to 1 if you have the hwloc library.])
-  HWLOC_REQUIRES=hwloc
-  AC_SUBST([STARPU_HAVE_HWLOC], [1])
-], [:])
-AC_SUBST(HWLOC_REQUIRES)
+AC_ARG_WITH([hwloc], [AS_HELP_STRING([--without-hwloc], [Disable hwloc (enabled by default)])])
+
+AS_IF([test "x$with_hwloc" != "xno"], [
+	PKG_CHECK_MODULES([HWLOC], [hwloc], [
+	  AC_DEFINE([STARPU_HAVE_HWLOC], [1], [Define to 1 if you have the hwloc library.])
+	  HWLOC_REQUIRES=hwloc
+	  AC_SUBST([STARPU_HAVE_HWLOC], [1])
+	], [:])
+	AC_SUBST(HWLOC_REQUIRES)
+])
 
 # is the header file f77.h available ?
 have_f77_h=yes