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| author | Joe Perches <joe@perches.com> | 2020-10-16 06:12:09 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-16 21:11:21 +0300 |
| commit | 99ca38c2aa7da5ab39e55f13fd425c6101903ccb (patch) | |
| tree | 2f209a09fbe8a7a1dc9a5dfe461b565476df9fa0 | |
| parent | c12093a11462b775a83ed600bf0036c8bef3e841 (diff) | |
| download | linux-99ca38c2aa7da5ab39e55f13fd425c6101903ccb.tar.xz | |
checkpatch: warn on self-assignments
The uninitialized_var() macro was removed recently via commit 63a0895d960a
("compiler: Remove uninitialized_var() macro") as it's not a particularly
useful warning and its use can "paper over real bugs".
Add a checkpatch test to warn on self-assignments as a means to avoid
compiler warnings and as a back-door mechanism to reproduce the old
uninitialized_var macro behavior.
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Denis Efremov <efremov@linux.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Link: https://lkml.kernel.org/r/afc2cffdd315d3e4394af149278df9e8af7f49f4.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rwxr-xr-x | scripts/checkpatch.pl | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 81c20557d974..5fe8762b1fae 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3899,6 +3899,17 @@ sub process { #ignore lines not being added next if ($line =~ /^[^\+]/); +# check for self assignments used to avoid compiler warnings +# e.g.: int foo = foo, *bar = NULL; +# struct foo bar = *(&(bar)); + if ($line =~ /^\+\s*(?:$Declare)?([A-Za-z_][A-Za-z\d_]*)\s*=/) { + my $var = $1; + if ($line =~ /^\+\s*(?:$Declare)?$var\s*=\s*(?:$var|\*\s*\(?\s*&\s*\(?\s*$var\s*\)?\s*\)?)\s*[;,]/) { + WARN("SELF_ASSIGNMENT", + "Do not use self-assignments to avoid compiler warnings\n" . $herecurr); + } + } + # check for dereferences that span multiple lines if ($prevline =~ /^\+.*$Lval\s*(?:\.|->)\s*$/ && $line =~ /^\+\s*(?!\#\s*(?!define\s+|if))\s*$Lval/) { |