[XEN] Define -fvisibility=hidden in CFLAGS to reduce -fpic cost
authorkaf24@firebug.cl.cam.ac.uk <kaf24@firebug.cl.cam.ac.uk>
Wed, 13 Sep 2006 12:52:03 +0000 (13:52 +0100)
committerkaf24@firebug.cl.cam.ac.uk <kaf24@firebug.cl.cam.ac.uk>
Wed, 13 Sep 2006 12:52:03 +0000 (13:52 +0100)
when compiling for x86/64.
Signed-off-by: Keir Fraser <keir@xensource.com>
xen/arch/x86/Rules.mk

index e91c8bf02d16d48ab953afab55b011c527a42e60..32c8e026951a9029cd2d3286a376d7916a04454a 100644 (file)
@@ -42,6 +42,9 @@ endif
 ifeq ($(TARGET_SUBARCH),x86_64)
 CFLAGS  += -mno-red-zone -fpic -fno-reorder-blocks
 CFLAGS  += -fno-asynchronous-unwind-tables
+# -fvisibility=hidden reduces -fpic cost, if it's available
+CFLAGS  += $(shell $(CC) -v --help 2>&1 | grep " -fvisibility=" | \
+             grep -q hidden && echo "-fvisibility=hidden")
 LDFLAGS += -m elf_x86_64
 x86_32 := n
 x86_64 := y