Re: /* compiler workaround */ - what was the issue?
- From
Ramsay Jones <ramsay@ramsayjones.plus.com>
- Date
- May 6, 2016, 18:05 UTC
- Message-ID
- <572CDCFF.9050607@ramsayjones.plus.com>
- In-Reply-To
- <51C902B1F7464CF2B58EB0E495F86BB5@PhilipOakley>
On 06/05/16 14:15, Philip Oakley wrote:
Show 32 quoted lines
> From: "Duy Nguyen" <pclouds@gmail.com> >> On Fri, May 6, 2016 at 4:41 AM, Junio C Hamano <gitster@pobox.com> wrote: >>> "Philip Oakley" <philipoakley@iee.org> writes: >>> >>>> int saved_namelen = saved_namelen; /* compiler workaround */ >>>> >>>> Which then becomes an MSVC compile warning C4700: uninitialized local >>>> variable. >>>> >>>> I'm wondering what was the compiler workaround being referred to? i.e. why >>>> does it need that tweak? There's no mention of the reason in the commit >>>> message. >>> >>> That was a fairly well-known workaround for GCC that issues a false >>> warning that variable is used before initialized. I thought we >>> stopped using it several years ago in new code after doing a bulk >>> sanitizing >> >> I guess that's 803a777 (cat-file: Fix an gcc -Wuninitialized warning - >> 2013-03-26) and more commits around that time. The split-index commit >> is in 2014. I must have missed the trend. >> >>> (I think the new recommended workaround was to initialise >>> such a variable to the nil value like '0' for integers). >> >> Yep. First Jeff removed the " = xxx" part from "xxx = xxx" then Ramsay >> added the " = NULL" back. So we probably just do "int saved_namelen = >> 0;" in this case. >> -- > Thanks, > > I'll try and work up a patch - probably next week as I'm away for the weekend.
Yeah, I don't remember why these were left over from the previous attempt to clean these up (maybe they conflicted with in-flight topics?), but I have had a patch hanging around ... :-D
The patch below applies to master (I haven't checked for any more additions).
ATB, Ramsay Jones
-- >8 -- From: Ramsay Jones <ramsay@ramsayjones.plus.com> Subject: [PATCH] -Wuninitialized: remove a gcc specific workaround
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> --- builtin/rev-list.c | 2 +- fast-import.c | 4 ++-- merge-recursive.c | 2 +- read-cache.c | 2 +- 4 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/builtin/rev-list.c b/builtin/rev-list.c index 275da0d..deae1f3 100644 --- a/builtin/rev-list.c +++ b/builtin/rev-list.c @@ -377,7 +377,7 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix) mark_edges_uninteresting(&revs, show_edge); if (bisect_list) { - int reaches = reaches, all = all; + int reaches = 0, all = 0; revs.commits = find_bisection(revs.commits, &reaches, &all, bisect_find_all); diff --git a/fast-import.c b/fast-import.c index 9fc7093..ca66d80 100644 --- a/fast-import.c +++ b/fast-import.c @@ -2935,7 +2935,7 @@ static void cat_blob(struct object_entry *oe, unsigned char sha1[20]) static void parse_get_mark(const char *p) { - struct object_entry *oe = oe; + struct object_entry *oe = NULL; char output[42]; /* get-mark SP <object> LF */ @@ -2952,7 +2952,7 @@ static void parse_get_mark(const char *p) static void parse_cat_blob(const char *p) { - struct object_entry *oe = oe; + struct object_entry *oe = NULL; unsigned char sha1[20]; /* cat-blob SP <object> LF */ diff --git a/merge-recursive.c b/merge-recursive.c index 06d31ed..9cecc24 100644 --- a/merge-recursive.c +++ b/merge-recursive.c @@ -1897,7 +1897,7 @@ int merge_recursive(struct merge_options *o, { struct commit_list *iter; struct commit *merged_common_ancestors; - struct tree *mrtree = mrtree; + struct tree *mrtree = NULL; int clean; if (show(o, 4)) { diff --git a/read-cache.c b/read-cache.c index d9fb78b..978d6b6 100644 --- a/read-cache.c +++ b/read-cache.c @@ -1870,7 +1870,7 @@ static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce, { int size; struct ondisk_cache_entry *ondisk; - int saved_namelen = saved_namelen; /* compiler workaround */ + int saved_namelen = 0; char *name; int result;
-- 2.8.0