1

I noticed that code size optimization flags (-Os and -Oz) are not supported in Flang. Is there a plan to add these? If so, is there any ongoing work happening now?

2

This is the first time I’ve heard someone request or use this feature in the context of Fortran. Is there a specific use case or motivation? Is the goal to minimize total binary size or improve icache behavior?

3

Binary size. I hit this while building SPEC CPU 2017. I used the same config file as I would do for gcc/gfortran and saw the error.

4

If you open an issue, there is a chance that someone will take care of this.

5

Thanks, will do.

6

Apologies for necro-bumping this, but I put up a PR that adds support for -Os/-Oz in flang. The behavior is identical to clang, and only affects the LLVM pass pipeline. I’m happy to tweak it if there is something more specific to Fortran that would be useful.

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