[BUG]: -flto=thin from CMAKE_INTERPROCEDURAL_OPTIMIZATION_CONFIG is not respected

[LE GARREC Vincent]

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What version (or hash if on master) of pybind11 are you using?

f33f6af

Problem description

I want to enable lto in Release mode only. I added set(CMAKE_INTERPROCEDURAL_OPTIMIZATION_RELEASE TRUE) in my CMakeLists.txt.

Since I didn't set CMAKE_INTERPROCEDURAL_OPTIMIZATION, line

pybind11/tools/pybind11Common.cmake

Line 397 in f33f6af

 if(NOT DEFINED CMAKE_INTERPROCEDURAL_OPTIMIZATION) 

think I didn't already enabled -flto=thin and add -flto. So when building in Release mode, I have : -flto=thin -flto.

I bypass the problem by setting THIN_LTO in pybind11_add_module.

Reproducible example code

No response

Is this a regression? Put the last known working version here if it is.

Not a regression