Clang Query Examples

01 Jason Turner "you are using optional wrong!"

Inspired by Jason Turners "you are using optional, variant,... wrong!". Can we detect it with clang-query?

cd 01_jt_wrong_optional/
./run.sh

Error while trying to load a compilation database:
Could not auto-detect compilation database for file "example.cpp"
No compilation database found in /home/mla/projects/clang-query-examples/01_jt_wrong_optional or any parent directory
fixed-compilation-database: Error while opening fixed database: No such file or directory
json-compilation-database: Error while opening JSON database: No such file or directory
Running without flags.

Match #1:

Binding for "root":
CXXConstructExpr 0x565195c18668 </home/mla/projects/clang-query-examples/01_jt_wrong_optional/example.cpp:19:12, col:21> 'std::optional<AStruct>' 'void (AStruct &&) noexcept(is_nothrow_constructible_v<AStruct, AStruct>)'
`-MaterializeTemporaryExpr 0x565195c130b8 <col:12, col:21> 'AStruct' xvalue
  `-CXXFunctionalCastExpr 0x565195c119a0 <col:12, col:21> 'AStruct' functional cast to AStruct <ConstructorConversion>
    `-CXXBindTemporaryExpr 0x565195c11980 <col:12, col:21> 'AStruct' (CXXTemporary 0x565195c11980)
      `-CXXConstructExpr 0x565195c11948 <col:12, col:21> 'AStruct' 'void (int)'
        `-ImplicitCastExpr 0x565195c11930 <col:20> 'int' <LValueToRValue>
          `-DeclRefExpr 0x565195c11910 <col:20> 'int' lvalue ParmVar 0x565195b955d8 'a' 'int'

Binding for "x":
RecordType 0x565195b76cd0 'AStruct'
`-CXXRecord 0x565195b76c38 'AStruct'

1 match.

Useful links

• AST Matcher docs

Editor support

Got the syntax.vim file from Here it may be out of date.

:source syntax.vim
:set filetype=clang-query