Commit Graph

7 Commits

Author SHA1 Message Date
Hans Wennborg 59ad150939 Revert r318456 "Issue -Wempty-body warnings for else blocks"
This caused warnings also when the if or else comes from macros. There was an
attempt to fix this in r318556, but that introduced new problems and was
reverted. Reverting this too until the whole issue is sorted.

> This looks like it was just an oversight.
>
> Fixes http://llvm.org/pr35319
>
> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@318456 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-svn: 318667
2017-11-20 17:48:54 +00:00
Hans Wennborg 9541975071 Revert r318556 "Loosen -Wempty-body warning"
It seems this somehow made -Wempty-body fire in some macro cases where
it didn't before, e.g.

  ../../third_party/ffmpeg/libavcodec/bitstream.c(169,5):  error: if statement has empty body [-Werror,-Wempty-body]
      ff_dlog(NULL, "new table index=%d size=%d\n", table_index, table_size);
      ^
  ../../third_party/ffmpeg\libavutil/internal.h(276,80):  note: expanded from macro 'ff_dlog'
  #   define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
                                                                                 ^
  ../../third_party/ffmpeg/libavcodec/bitstream.c(169,5):  note: put the
  semicolon on a separate line to silence this warning

Reverting until this can be figured out.

> Do not show it when `if` or `else` come from macros.
> E.g.,
>
>     #define USED(A) if (A); else
>     #define SOME_IF(A) if (A)
>
>     void test() {
>       // No warnings are shown in those cases now.
>       USED(0);
>       SOME_IF(0);
>     }
>
> Patch by Ilya Biryukov!
>
> Differential Revision: https://reviews.llvm.org/D40185

llvm-svn: 318665
2017-11-20 17:38:16 +00:00
Reid Kleckner c0a81071d3 Loosen -Wempty-body warning
Do not show it when `if` or `else` come from macros.
E.g.,

    #define USED(A) if (A); else
    #define SOME_IF(A) if (A)

    void test() {
      // No warnings are shown in those cases now.
      USED(0);
      SOME_IF(0);
    }

Patch by Ilya Biryukov!

Differential Revision: https://reviews.llvm.org/D40185

llvm-svn: 318556
2017-11-17 21:33:28 +00:00
Reid Kleckner adefb760a8 Issue -Wempty-body warnings for else blocks
This looks like it was just an oversight.

Fixes http://llvm.org/pr35319

llvm-svn: 318456
2017-11-16 21:26:18 +00:00
Dmitri Gribenko ad80af8f19 -Wempty-body: fix false negative triggered by macros
When if statement condition ended in a macro:

    if (ptr == NULL);

the check used to consider the definition location of NULL, instead of the
current line.

Patch by Manasij Mukherjee.

llvm-svn: 232295
2015-03-15 01:08:23 +00:00
Eli Friedman 0834a4b901 Make Preprocessor::Lex non-recursive.
Before this patch, Lex() would recurse whenever the current lexer changed (e.g.
upon entry into a macro). This patch turns the recursion into a loop: the
various lex routines now don't return a token when the current lexer changes,
and at the top level Preprocessor::Lex() now loops until it finds a token.
Normally, the recursion wouldn't end up being very deep, but the recursion depth
can explode in edge cases like a bunch of consecutive macros which expand to
nothing (like in the testcase test/Preprocessor/macro_expand_empty.c in this
patch).

<rdar://problem/14569770>

llvm-svn: 190980
2013-09-19 00:41:32 +00:00
Dmitri Gribenko 800ddf3dda Generalize -Wempty-body: warn when statement body is empty (closes: PR11329)
* if, switch, range-based for: warn if semicolon is on the same line.
* for, while: warn if semicolon is on the same line and either next
statement is compound statement or next statement has more
indentation.

Replacing the semicolon with {} or moving the semicolon to the next
line will always silence the warning.

Tests from SemaCXX/if-empty-body.cpp merged into SemaCXX/warn-empty-body.cpp.

llvm-svn: 150515
2012-02-14 22:14:32 +00:00