[cfe-dev] Speed up debug version of LibTooling AST parsing

[Jan Ryšavý via cfe-dev]

Thank you for this idea. Trouble with LibTooling in Release build is we must use Release build also for our utility (Windows executable), otherwise we are receiving following RTL conflicts:

1>clangAST.lib(DeclarationName.obj) : error LNK2038: mismatch detected for 'RuntimeLibrary': value 'MD_DynamicRelease' doesn't match value 'MDd_DynamicDebug' in CmdLineUtils.obj
1>clangAST.lib(ASTTypeTraits.obj) : error LNK2038: mismatch detected for 'RuntimeLibrary': value 'MD_DynamicRelease' doesn't match value 'MDd_DynamicDebug' in CmdLineUtils.obj
etc.

Of course we can turn off optimizations and debug in Release build...

Best regards
Jan Rysavy

On 17.02.2020 15:13, Whisperity wrote:
> Unless you need the actual Debug build for anything, maybe try sticking to assertions and a release build? (-DLLVM_ENABLE_ASSERTIONS=ON -DCMAKE_BUILD_TYPE=Release) Release build is fast, small, and with enough assertions (and maybe putting "llvm/Support/Debug.h" into the file and calling the frontend with -debug?) you could get most of the stuff you need for debugging.
> 
> Jan Ryšavý via cfe-dev <cfe-dev at lists.llvm.org <mailto:cfe-dev at lists.llvm.org>> ezt írta (időpont: 2020. febr. 17., H, 10:19):
> 
>     We are using Clang LibTooling for source-to-source conversion. Size of converted headers is around 10MB.
> 
>     Release version of our conversion utility works fine, but debug version is spending 20 seconds in clang::ParseAST.
> 
>     Is there any chance how to speed up parsing, for example using precompiled headers (or storing parsed AST)?
> 
>     Could you please point me in the right direction?
> 
>     Best regards
>     Jan Rysavy
>     _______________________________________________
>     cfe-dev mailing list
>     cfe-dev at lists.llvm.org <mailto:cfe-dev at lists.llvm.org>
>     https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
>