diff --git a/testsuite/tests/hsc2hs/Makefile b/testsuite/tests/hsc2hs/Makefile
index d0b2d249c3fdde021b8f7c29f6894b7aa52a6c45..95b011c85d653b8150d0001e4674524f4424f0d8 100644
--- a/testsuite/tests/hsc2hs/Makefile
+++ b/testsuite/tests/hsc2hs/Makefile
@@ -52,9 +52,9 @@ T11004:
 T12504:
 	'$(HSC2HS)' $(HSC2HS_OPTS) T12504/path/to/$@.hsc
 ifeq "$(WINDOWS)" "YES"
-	grep '{-# LINE 1 \"T12504\\\\path\\\\to\\\\$@\.hsc\" #-}' T12504/path/to/$@.hs
+	grep '{-# LINE 1 "T12504\\\\path\\\\to\\\\$@\.hsc" #-}' T12504/path/to/$@.hs
 else
-	grep '{-# LINE 1 \"T12504/path/to/$@\.hsc\" #-}' T12504/path/to/$@.hs
+	grep '{-# LINE 1 "T12504/path/to/$@\.hsc" #-}' T12504/path/to/$@.hs
 endif
 
 .PHONY: T15758
diff --git a/testsuite/tests/numeric/should_run/Makefile b/testsuite/tests/numeric/should_run/Makefile
index 26ec990fee35c0436f2b2cc465059b151f028c55..23f4456dcae527971dc9b8307c40dea57d30a3a8 100644
--- a/testsuite/tests/numeric/should_run/Makefile
+++ b/testsuite/tests/numeric/should_run/Makefile
@@ -6,5 +6,5 @@ include $(TOP)/mk/test.mk
 T7014:
 	rm -f T7014.simpl T7014.o T7014.hi
 	'$(TEST_HC)' -Wall -v0 -O --make T7014.hs -fforce-recomp -ddump-simpl > T7014.simpl
-	! grep -q -f T7014.primops T7014.simpl
+	! grep -Eq -f T7014.primops T7014.simpl
 	./T7014
diff --git a/testsuite/tests/numeric/should_run/T7014.primops b/testsuite/tests/numeric/should_run/T7014.primops
index 3243666dbc5b406e91f37b8843deb7bf68e10d75..8277db5c328281f3cf2ddc1482ce297e4a7a8001 100644
--- a/testsuite/tests/numeric/should_run/T7014.primops
+++ b/testsuite/tests/numeric/should_run/T7014.primops
@@ -2,7 +2,7 @@ and#
 or#
 uncheckedShift.*#
 \+#
-\-#
+-#
 \*#
 quotInt#
 remInt#
diff --git a/testsuite/tests/simplCore/should_compile/Makefile b/testsuite/tests/simplCore/should_compile/Makefile
index ffc56f8ee47718ad6bb2776f89232ca5f8c58b00..0583cb496e09a435c826f5f17d22e95de6474076 100644
--- a/testsuite/tests/simplCore/should_compile/Makefile
+++ b/testsuite/tests/simplCore/should_compile/Makefile
@@ -254,7 +254,7 @@ str-rules:
 # g should have been collapsed into one defininition by CSE.
 .PHONY: T13340
 T13340:
-	'$(TEST_HC)' $(TEST_HC_OPTS) -c -O T13340.hs -ddump-simpl -dsuppress-all | grep -c '\+#'
+	'$(TEST_HC)' $(TEST_HC_OPTS) -c -O T13340.hs -ddump-simpl -dsuppress-all | grep -Ec '\+#'
 
 
 # We expect to see all dictionaries specialized away.