diff --git a/lib/common/Makefile.am b/lib/common/Makefile.am
index 68a8e9ab5c..7b4255a072 100644
--- a/lib/common/Makefile.am
+++ b/lib/common/Makefile.am
@@ -1,112 +1,119 @@
 #
 # Copyright 2004-2022 the Pacemaker project contributors
 #
 # The version control history for this file may have further details.
 #
 # This source code is licensed under the GNU General Public License version 2
 # or later (GPLv2+) WITHOUT ANY WARRANTY.
 #
 include $(top_srcdir)/mk/common.mk
 
 AM_CPPFLAGS		+= -I$(top_builddir)/lib/gnu -I$(top_srcdir)/lib/gnu
 
 ## libraries
 lib_LTLIBRARIES	= libcrmcommon.la
 check_LTLIBRARIES = libcrmcommon_test.la
 
 # Disable -Wcast-qual if used, because we do some hacky casting,
 # and because libxml2 has some signatures that should be const but aren't
 # for backward compatibility reasons.
 
 # s390 needs -fPIC 
 # s390-suse-linux/bin/ld: .libs/ipc.o: relocation R_390_PC32DBL against `__stack_chk_fail@@GLIBC_2.4' can not be used when making a shared object; recompile with -fPIC
 
 CFLAGS		= $(CFLAGS_COPY:-Wcast-qual=) -fPIC
 
 # Without "." here, check-recursive will run through the subdirectories first
 # and then run "make check" here.  This will fail, because there's things in
 # the subdirectories that need check_LTLIBRARIES built first.  Adding "." here
 # changes the order so the subdirectories are processed afterwards.
 SUBDIRS = . tests
 
 noinst_HEADERS		= crmcommon_private.h mock_private.h
 
 libcrmcommon_la_LDFLAGS	= -version-info 43:1:9
 
 libcrmcommon_la_CFLAGS	= $(CFLAGS_HARDENED_LIB)
 libcrmcommon_la_LDFLAGS	+= $(LDFLAGS_HARDENED_LIB)
 
 libcrmcommon_la_LIBADD	= @LIBADD_DL@ $(top_builddir)/lib/gnu/libgnu.la
 
 # If configured with --with-profiling or --with-coverage, BUILD_PROFILING will
 # be set and -fno-builtin will be added to the CFLAGS.  However, libcrmcommon
 # uses the fabs() function which is normally supplied by gcc as one of its
 # builtins.  Therefore we need to explicitly link against libm here or the
 # tests won't link.
 if BUILD_PROFILING
 libcrmcommon_la_LIBADD	+= -lm
 endif
 
 # Use += rather than backlashed continuation lines for parsing by bumplibs
 libcrmcommon_la_SOURCES	=
 libcrmcommon_la_SOURCES	+= acl.c
 libcrmcommon_la_SOURCES	+= agents.c
 libcrmcommon_la_SOURCES	+= alerts.c
 libcrmcommon_la_SOURCES	+= attrs.c
 libcrmcommon_la_SOURCES	+= cib.c
 if BUILD_CIBSECRETS
 libcrmcommon_la_SOURCES	+= cib_secrets.c
 endif
 libcrmcommon_la_SOURCES	+= cmdline.c
 libcrmcommon_la_SOURCES	+= digest.c
 libcrmcommon_la_SOURCES	+= health.c
 libcrmcommon_la_SOURCES	+= io.c
 libcrmcommon_la_SOURCES	+= ipc_attrd.c
 libcrmcommon_la_SOURCES	+= ipc_client.c
 libcrmcommon_la_SOURCES	+= ipc_common.c
 libcrmcommon_la_SOURCES	+= ipc_controld.c
 libcrmcommon_la_SOURCES	+= ipc_pacemakerd.c
 libcrmcommon_la_SOURCES 	+= ipc_schedulerd.c
 libcrmcommon_la_SOURCES	+= ipc_server.c
 libcrmcommon_la_SOURCES	+= iso8601.c
 libcrmcommon_la_SOURCES	+= lists.c
 libcrmcommon_la_SOURCES	+= logging.c
 libcrmcommon_la_SOURCES	+= mainloop.c
 libcrmcommon_la_SOURCES	+= messages.c
 libcrmcommon_la_SOURCES	+= nvpair.c
 libcrmcommon_la_SOURCES	+= operations.c
 libcrmcommon_la_SOURCES	+= options.c
 libcrmcommon_la_SOURCES	+= output.c
 libcrmcommon_la_SOURCES	+= output_html.c
 libcrmcommon_la_SOURCES	+= output_log.c
 libcrmcommon_la_SOURCES	+= output_none.c
 libcrmcommon_la_SOURCES	+= output_text.c
 libcrmcommon_la_SOURCES	+= output_xml.c
 libcrmcommon_la_SOURCES	+= patchset.c
 libcrmcommon_la_SOURCES	+= pid.c
 libcrmcommon_la_SOURCES	+= procfs.c
 libcrmcommon_la_SOURCES	+= remote.c
 libcrmcommon_la_SOURCES	+= results.c
 libcrmcommon_la_SOURCES	+= schemas.c
 libcrmcommon_la_SOURCES	+= scores.c
 libcrmcommon_la_SOURCES	+= strings.c
 libcrmcommon_la_SOURCES	+= utils.c
 libcrmcommon_la_SOURCES	+= watchdog.c
 libcrmcommon_la_SOURCES	+= xml.c
 libcrmcommon_la_SOURCES	+= xpath.c
 
 #
 # libcrmcommon_test is used only with unit tests, so we can mock system calls.
 # See mock.c for details.
 #
 
 libcrmcommon_test_la_SOURCES	= $(libcrmcommon_la_SOURCES)
 libcrmcommon_test_la_SOURCES	+= mock.c
 libcrmcommon_test_la_LDFLAGS	= $(LDFLAGS_HARDENED_LIB)
-libcrmcommon_test_la_CFLAGS	= $(libcrmcommon_la_CFLAGS)
-libcrmcommon_test_la_LIBADD	= $(libcrmcommon_la_LIBADD) -lcmocka
+# If GCC emits a builtin function in place of something we've mocked up, that will
+# get used instead of the mocked version which leads to unexpected test results.  So
+# disable all builtins.  Older versions of GCC (at least, on RHEL7) will still emit
+# replacement code for strdup (and possibly other functions) unless -fno-inline is
+# also added.
+libcrmcommon_test_la_CFLAGS	= $(libcrmcommon_la_CFLAGS) -fno-builtin -fno-inline
+# If -fno-builtin is used, -lm also needs to be added.  See the comment at
+# BUILD_PROFILING above.
+libcrmcommon_test_la_LIBADD	= $(libcrmcommon_la_LIBADD) -lcmocka -lm
 
 nodist_libcrmcommon_test_la_SOURCES = $(nodist_libcrmcommon_la_SOURCES)
 
 clean-generic:
 	rm -f *.log *.debug *.xml *~