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[PATCH] commit.h: rearrange 'index' to shrink struct commit

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
May 11, 2018, 17:20 UTC
Message-ID
<20180511172054.7684-1-pclouds@gmail.com>

On linux 64-bit architecture, pahole finds that there's a 4 bytes padding after 'index'. Moving it to the end reduces this struct's size from 72 to 64 bytes (because of another 4 bytes padding after graph_pos). On linux 32-bit, the struct size remains 52 bytes like before.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 commit.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/commit.h b/commit.h
index e57ae4b583..fd1cbe7263 100644
--- a/commit.h
+++ b/commit.h
@@ -19,11 +19,11 @@ struct commit_list {
 struct commit {
 	struct object object;
 	void *util;
-	unsigned int index;
 	timestamp_t date;
 	struct commit_list *parents;
 	struct tree *tree;
 	uint32_t graph_pos;
+	unsigned int index;
 };
 
 extern int save_commit_buffer;
-- 
2.17.0.705.g3525833791
Next: Junio C Hamano
Message 1 of 2 in “commit.h: rearrange 'index' to shrink struct commit”
  1. commit.h: rearrange 'index' to shrink struct commitNguyễn Thái Ngọc Duy, May 11, 2018
  2. Junio C HamanoMay 13, 2018

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