Subject: [PATCH] Fix an "variable might be used uninitialized" gcc warning

From: Ramsay Jones <[email-masked]>
Date: Fri, 16 Dec 2011 22:44:38 +0000

In particular, gcc issues the following warning:

        CC builtin/checkout.o
    builtin/checkout.c: In function `cmd_checkout':
    builtin/checkout.c:160: warning: 'mode' might be used uninitialized \
        in this function

However, the analysis performed by gcc is too conservative, in this
case, since the mode variable will not be used uninitialised. Note that,
if the mode variable is not set in the loop, then "threeway[1]" will
also still be set to the null SHA1. This will then result in control
leaving the function, almost directly after the loop, well before the
potential use in the call to make_cache_entry().

In order to suppress the warning, we initialise the mode variable to
zero in it's declaration.

Signed-off-by: Ramsay Jones <[email-masked]>
---

Just in case you haven't found the time to apply your own patch!

[Note that only 2 out of the 3 versions of gcc I use issues this
warning]

ATB,
Ramsay Jones

 builtin/checkout.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/builtin/checkout.c b/builtin/checkout.c
index 787d468..f1984d9 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -157,7 +157,7 @@ static int checkout_merged(int pos, struct checkout *state)
 	unsigned char sha1[20];
 	mmbuffer_t result_buf;
 	unsigned char threeway[3][20];
-	unsigned mode;
+	unsigned mode = 0;
 
 	memset(threeway, 0, sizeof(threeway));
 	while (pos < active_nr) {
-- 
1.7.8