diff --git a/exp-drd/Makefile.am b/exp-drd/Makefile.am
index 04d90160b..547d9490a 100644
--- a/exp-drd/Makefile.am
+++ b/exp-drd/Makefile.am
@@ -26,12 +26,15 @@ else
 VGPRELOAD_DRD_SOURCES_COMMON = drd_pthread_intercepts.c
 endif
 
-AM_CFLAGS_X86_LINUX   += -Wsign-compare -Winline -O2 -DCHECK_FORMAT_STRINGS
-AM_CFLAGS_AMD64_LINUX += -Wsign-compare -Winline -O2 -DCHECK_FORMAT_STRINGS
-AM_CFLAGS_PPC32_LINUX += -Wsign-compare -Winline -O2 -DCHECK_FORMAT_STRINGS
-AM_CFLAGS_PPC64_LINUX += -Wsign-compare -Winline -O2 -DCHECK_FORMAT_STRINGS
-AM_CFLAGS_PPC32_AIX5  += -Wsign-compare -Winline -O2 -DCHECK_FORMAT_STRINGS
-AM_CFLAGS_PPC64_AIX5  += -Wsign-compare -Winline -O2 -DCHECK_FORMAT_STRINGS
+DRD_CFLAGS=@FLAG_W_EXTRA@ -Winline -Wno-unused-parameter \
+           -O2 -DCHECK_FORMAT_STRINGS
+
+AM_CFLAGS_X86_LINUX   += $(DRD_CFLAGS)
+AM_CFLAGS_AMD64_LINUX += $(DRD_CFLAGS)
+AM_CFLAGS_PPC32_LINUX += $(DRD_CFLAGS)
+AM_CFLAGS_PPC64_LINUX += $(DRD_CFLAGS)
+AM_CFLAGS_PPC32_AIX5  += $(DRD_CFLAGS)
+AM_CFLAGS_PPC64_AIX5  += $(DRD_CFLAGS)
 
 vgpreload_exp_drd_x86_linux_so_SOURCES      = $(VGPRELOAD_DRD_SOURCES_COMMON)
 vgpreload_exp_drd_x86_linux_so_CPPFLAGS     = $(AM_CPPFLAGS_X86_LINUX)