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Bug 1725

Summary: Slow MSVC compile times
Product: Eigen Reporter: Björn Piltz <bjornpiltz>
Component: GeneralAssignee: Nobody <eigen.nobody>
Status: NEW ---    
Severity: Unknown CC: bjornpiltz, chtz, gael.guennebaud, jacob.benoit.1
Priority: Normal    
Version: 3.3 (current stable)   
Hardware: All   
OS: Windows   

Description Björn Piltz 2019-06-17 15:52:55 UTC
It seems MSVC has a problem with Eigen's massive use of inlining. Some tests which take minutes to compile with GCC/clang take up to an hour to compile with MSVC 2017 as reported here:

The timings for MSVC 2019 are better, but not great.

I have set up some test scripts here:

To recreate the tables, compile Eigen3.sln in release mode from within Visual Studio and process the build log with eigen_compilation_time_msvc.Rmd.

I would suggest creating a minimal example, which can be reported to Microsoft as this is obviously an issue on their side.
Comment 1 Björn Piltz 2019-06-17 15:55:04 UTC
The link to the mailing list should be
Comment 3 Nobody 2019-12-04 18:41:24 UTC
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