git-compat-util: st_add4: work around gcc 4.2.x compiler crash

Although changes by 5b442c4 (tree-diff: catch integer overflow in combine_diff_path allocation, 2016-02-19) are perfectly valid, they unfortunately trigger an internal compiler error in gcc 4.2.x: combine-diff.c: In function 'diff_tree_combined': combine-diff.c:1391: internal compiler error: Segmentation fault: 11 Experimentation reveals that changing st_add4()'s argument evaluation order is sufficient to sidestep this problem. Although st_add3() does not trigger the compiler bug, for style consistency, change its argument evaluation order to match. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Eric Sunshine committed Mar 21, 2016 at 00:35 UTC d616fbf256ef3102669d450ddadd8469fefcf95c
1 file changed +2 -2
git-compat-util.h
+2 -2
@@ -713,8 +713,8 @@ static inline size_t st_add(size_t a, size_t b)
713 (uintmax_t)a, (uintmax_t)b);
714 return a + b;
715 }
716 -#define st_add3(a,b,c) st_add((a),st_add((b),(c)))
717 -#define st_add4(a,b,c,d) st_add((a),st_add3((b),(c),(d)))
716 +#define st_add3(a,b,c) st_add(st_add((a),(b)),(c))
717 +#define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
718
719 static inline size_t st_mult(size_t a, size_t b)
720 {