Diagnostic enhancement: "auto" in lambda expression under -std=c++11 (original) (raw)

Extended Description

Hi, all.

"auto" used in lambda expression is a c++14 extension, but clang doesn't emit the appropriate diagnostic message about it.

For example,

$cat test.cc int main(){ auto var = {}; return 0; }

$clang++ -std=c++11 -c test.cc
test.cc:2:19: error: 'auto' not allowed in lambda parameter
    auto var = [](auto){};
                  ^~~~
1 error generated.

I guess clang should give a more specific diagnostic about this like GCC.

$g++ -std=c++11 -c test.cc
test.cc: In function ‘int main()’:
test.cc:2:19: error: use of ‘auto’ in lambda parameter declaration only available with ‘-std=c++14’ or ‘-std=gnu++14’
    2 |     auto var = [](auto){};
      |                   ^~~~

Just a small enhancement I guess, please understand if anything I stated is unsuitable.

Thanks,
Haoxin