[PATCH] D16535: [clang-tidy] Check to find unintended semicolons that changes the semantics.

[Kirill Bobyrev via cfe-commits]

omtcyf0 added a comment.

In http://reviews.llvm.org/D16535#362689, @alexfh wrote:

> In http://reviews.llvm.org/D16535#362685, @omtcyf0 wrote:
>
> > @xazax.hun did you actually run the tool on the LLVM codebase?
> >
> > Because this check generates **tons** of false-positive reports during codebase analysis.
> >
> > See the minimal example below.
> >
> >   omtcyf0-laptop:playground omtcyf0$ cat main.cpp 
> >   #include <vector>
> >  
> >   int main() {
> >     std::vector<int> numbers = {1, 2, 3, 4, 5, 6};
> >     for (std::vector<int>::iterator it = std::begin(numbers),
> >                                     end = std::end(numbers);
> >          it != end; ++it) {
> >       (*it)++;
> >     }
> >     return 0;
> >   }
> >   omtcyf0-laptop:playground omtcyf0$ /Users/omtcyf0/Documents/dev/build/Release/llvm/bin/clang-tidy -checks=misc-suspicious-semicolon main.cpp 
> >   Error while trying to load a compilation database:
> >   Could not auto-detect compilation database for file "main.cpp"
> >   No compilation database found in /Users/omtcyf0/Documents/dev/playground or any parent directory
> >   json-compilation-database: Error while opening JSON database: No such file or directory
> >   Running without flags.
> >   1 warning and 1 error generated.
> >   Error while processing /Users/omtcyf0/Documents/dev/playground/main.cpp.
> >   /Users/omtcyf0/Documents/dev/playground/main.cpp:6:17: warning: potentially unintended semicolon [misc-suspicious-semicolon]
> >          it != end; ++it) {
> >                   ^
> >   /usr/include/wchar.h:89:10: error: 'stdarg.h' file not found [clang-diagnostic-error]
> >   #include <stdarg.h>
> >            ^
> >
> >
> > And this is happening all over the LLVM codebase, because there is nothing bad there.
> >
> > Can you please fix that?
>
>
> Kirill, the problem in your case may be related to the check seeing incomplete AST due to compilation errors. Can you append `-- -std=c++11` to your clang-tidy invocation and try again whether it will be able to parse the file completely (i.e. without any "file not found" and other compilation errors)?


Yes, you're right, it does suppress the warning.

However, running vanilla `run-clang-tidy.py` on the LLVM codebase still outputs such issues. Is it the `run-clang-tidy.py`'s fault? The compilation database contains the -std=c++11 specifiers, I assumed this gets added to the clang-tidy options while performing analysis of these sources, doesn't it?


Repository:
  rL LLVM

http://reviews.llvm.org/D16535