[git commit] build system: combat gcc zealotry in data alignment

[Denys Vlasenko]

commit: https://git.busybox.net/busybox/commit/?id=db793480cb8ec3e5f878d1ec18b6ed5010c85e85
branch: https://git.busybox.net/busybox/commit/?id=refs/heads/master

   text	   data	    bss	    dec	    hex	filename
1020934	    559	   5052	1026545	  fa9f1	busybox_old
1020750	    559	   5052	1026361	  fa939	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 arch/i386/Makefile | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/i386/Makefile b/arch/i386/Makefile
index 425361fd9..2fa008fa7 100644
--- a/arch/i386/Makefile
+++ b/arch/i386/Makefile
@@ -11,3 +11,11 @@ ifeq ($(CONFIG_STACK_OPTIMIZATION_386),y)
 # from aligning stack to 16 bytes. (Which is gcc's way of supporting SSE).
 CFLAGS += $(call cc-option,-mpreferred-stack-boundary=2,)
 endif
+
+# "Control how GCC aligns variables.
+# Supported values for type are compat uses increased alignment value
+# compatible uses GCC 4.8 and earlier, abi uses alignment value as specified by the psABI,
+# and cacheline uses increased alignment value to match the cache line size.
+# compat is the default."
+# "abi" seems to be somewhat successful in preventing oversealous data alignment.
+CFLAGS += $(call cc-option,-malign-data=abi,)