3 files changed, 11 insertions, 1 deletions
diff --git a/Makefile b/Makefile
index 6be584f536..82ab2f78f6 100644
--- a/Makefile
+++ b/Makefile
@@ -18,6 +18,13 @@
 MAKEFLAGS += --no-builtin-rules
 .SUFFIXES:
 
+
+# -----------------------------------------------------------------------------
+# Sanitize environment
+
+# See Trac #11530
+export GREP_OPTIONS :=
+
 ifneq "$(filter maintainer-clean distclean clean clean_% help,$(MAKECMDGOALS))" ""
 -include mk/config.mk
 else
diff --git a/boot b/boot
index 18d43aabda..45f5bf06c2 100755
--- a/boot
+++ b/boot
@@ -11,6 +11,9 @@ my %required_tag;
 my $validate;
 my $curdir;
 
+# See Trac #11530
+$ENV{GREP_OPTIONS} = '';
+
 $required_tag{"-"} = 1;
 $validate = 0;
 
diff --git a/ghc.mk b/ghc.mk
index 8f4aaba491..4034a92d4e 100644
--- a/ghc.mk
+++ b/ghc.mk
@@ -92,7 +92,7 @@ $(error Your make does not support abspath. You need GNU make >= 3.81)
 endif
 ##################################################
 
-
+# -----------------------------------------------------------------------------
 # Catch make if it runs away into an infinite loop
 ifeq      "$(MAKE_RESTARTS)" ""
 else ifeq "$(MAKE_RESTARTS)" "1"