diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index 7cbdeb589b..d98bc07143 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -115,7 +115,9 @@ backend_src = $(top_srcdir)/src/backend
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
 ifeq (,$(filter aix solaris,$(PORTNAME)))
-	! nm -A -u $< 2>/dev/null | grep -v __cxa_atexit | grep exit
+	@if nm -a -u $< 2>/dev/null | grep -v __cxa_atexit | grep exit; then \
+		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
+	fi
 endif
 endif
 	touch $@