diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 8f05840821..ab74535918 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -444,11 +444,19 @@ with_temp_install = \
 
 ifeq ($(enable_tap_tests),yes)
 
+ifndef PGXS
 define prove_installcheck
 rm -rf '$(CURDIR)'/tmp_check
 $(MKDIR_P) '$(CURDIR)'/tmp_check
 cd $(srcdir) && TESTDIR='$(CURDIR)' PATH="$(bindir):$$PATH" PGPORT='6$(DEF_PGPORT)' top_builddir='$(CURDIR)/$(top_builddir)' PG_REGRESS='$(CURDIR)/$(top_builddir)/src/test/regress/pg_regress' REGRESS_SHLIB='$(abs_top_builddir)/src/test/regress/regress$(DLSUFFIX)' $(PROVE) $(PG_PROVE_FLAGS) $(PROVE_FLAGS) $(if $(PROVE_TESTS),$(PROVE_TESTS),t/*.pl)
 endef
+else # PGXS case
+define prove_installcheck
+rm -rf '$(CURDIR)'/tmp_check
+$(MKDIR_P) '$(CURDIR)'/tmp_check
+cd $(srcdir) && TESTDIR='$(CURDIR)' PATH="$(bindir):$$PATH" PGPORT='6$(DEF_PGPORT)' top_builddir='$(top_builddir)' PG_REGRESS='$(top_builddir)/src/test/regress/pg_regress' $(PROVE) $(PG_PROVE_FLAGS) $(PROVE_FLAGS) $(if $(PROVE_TESTS),$(PROVE_TESTS),t/*.pl)
+endef
+endif # PGXS
 
 define prove_check
 rm -rf '$(CURDIR)'/tmp_check