fs/proc: Add compiler check for -Wno-override-init to support gcc < 4.2

With gcc < 4.2 (e.g. 4.1.2):

      CC      fs/proc/task_mmu.o
    cc1: error: unrecognized command line option "-Wno-override-init"

To fix this, only enable the compiler option when it is actually
supported by the compiler.

Fixes: ca52953f5f24 ("fs/proc/task_mmu.c: suppress compilation warnings with W=1")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/Makefile b/fs/proc/Makefile
index a8c1360..12c6922 100644 (file)
--- a/fs/proc/Makefile
+++ b/fs/proc/Makefile
@@ -4,7 +4,7 @@
 
 obj-y   += proc.o
 
-CFLAGS_task_mmu.o      += -Wno-override-init
+CFLAGS_task_mmu.o      += $(call cc-option,-Wno-override-init,)
 proc-y                 := nommu.o task_nommu.o
 proc-$(CONFIG_MMU)     := task_mmu.o