Messages in this thread Patch in this message | | | From | Jason Yan <> | Subject | [PATCH] erofs: Eliminate usage of uninitialized_var() macro | Date | Mon, 15 Jun 2020 12:01:41 +0800 |
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This is an effort to eliminate the uninitialized_var() macro[1].
The use of this macro is the wrong solution because it forces off ANY analysis by the compiler for a given variable. It even masks "unused variable" warnings.
Quoted from Linus[2]:
"It's a horrible thing to use, in that it adds extra cruft to the source code, and then shuts up a compiler warning (even the _reliable_ warnings from gcc)."
The gcc option "-Wmaybe-uninitialized" has been disabled and this change will not produce any warnnings even with "make W=1".
[1] https://github.com/KSPP/linux/issues/81 [2] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Cc: Kees Cook <keescook@chromium.org> Cc: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jason Yan <yanaijie@huawei.com> --- fs/erofs/data.c | 4 ++-- fs/erofs/zdata.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/erofs/data.c b/fs/erofs/data.c index 64b56c7df023..d0542151e8c4 100644 --- a/fs/erofs/data.c +++ b/fs/erofs/data.c @@ -265,7 +265,7 @@ static inline struct bio *erofs_read_raw_page(struct bio *bio, */ static int erofs_raw_access_readpage(struct file *file, struct page *page) { - erofs_off_t uninitialized_var(last_block); + erofs_off_t last_block; struct bio *bio; trace_erofs_readpage(page, true); @@ -282,7 +282,7 @@ static int erofs_raw_access_readpage(struct file *file, struct page *page) static void erofs_raw_access_readahead(struct readahead_control *rac) { - erofs_off_t uninitialized_var(last_block); + erofs_off_t last_block; struct bio *bio = NULL; struct page *page; diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index be50a4d9d273..24a26aaf847f 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1161,7 +1161,7 @@ static void z_erofs_submit_queue(struct super_block *sb, struct z_erofs_decompressqueue *q[NR_JOBQUEUES]; void *bi_private; /* since bio will be NULL, no need to initialize last_index */ - pgoff_t uninitialized_var(last_index); + pgoff_t last_index; unsigned int nr_bios = 0; struct bio *bio = NULL; -- 2.25.4
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