diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index b5fd72a4ac..8abdb092c2 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -143,11 +143,13 @@ install: all installdirs install-lib
 test-build:
 	$(MAKE) -C test all
 
+check installcheck: export PATH := $(CURDIR)/test:$(PATH)
+
 check: test-build all
-	PATH="$(CURDIR)/test:$$PATH" && $(prove_check)
+	$(prove_check)
 
 installcheck: test-build all
-	PATH="$(CURDIR)/test:$$PATH" && $(prove_installcheck)
+	$(prove_installcheck)
 
 installdirs: installdirs-lib
 	$(MKDIR_P) '$(DESTDIR)$(includedir)' '$(DESTDIR)$(includedir_internal)' '$(DESTDIR)$(datadir)'