From 4a5de8dd79879d737e172a5d7e4196c6bf99e57d Mon Sep 17 00:00:00 2001 From: David Barr Date: Fri, 1 Jun 2012 00:41:25 +1000 Subject: [PATCH] vcs-svn: avoid self-assignment in dummy initialization of pre_off Without this change, clang complains: vcs-svn/svndiff.c:298:3: warning: Assigned value is garbage or undefined off_t pre_off = pre_off; /* stupid GCC... */ ^ ~~~~~~~ This code uses an old and common idiom for suppressing an "uninitialized variable" warning, and clang is wrong to warn about it. The idiom tells the compiler to leave the variable uninitialized, which saves a few bytes of code size, and, more importantly, allows valgrind to check at runtime that the variable is properly initialized by the time it is used. But MSVC and clang do not know that idiom, so let's avoid it in vcs-svn/ code. Initialize pre_off to -1, a recognizably meaningless value, to allow future code changes that cause pre_off to be used before it is initialized to be caught early. Signed-off-by: David Barr Signed-off-by: Jonathan Nieder --- vcs-svn/svndiff.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/vcs-svn/svndiff.c b/vcs-svn/svndiff.c index 1647c1a780..c89d9623f4 100644 --- a/vcs-svn/svndiff.c +++ b/vcs-svn/svndiff.c @@ -295,7 +295,7 @@ int svndiff0_apply(struct line_buffer *delta, off_t delta_len, if (read_magic(delta, &delta_len)) return -1; while (delta_len) { /* For each window: */ - off_t pre_off = pre_off; /* stupid GCC... */ + off_t pre_off = -1; size_t pre_len; if (read_offset(delta, &pre_off, &delta_len) ||