Can I use LLVM's -fstack-size-section with Zig

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1

LLVM has a handy option, -fstack-size-section, which includes an elf section with stack sizes of all functions:

https://clang.llvm.org/docs/ClangCommandLineReference.html#cmdoption-clang-fstack-size-section

Is there some way I can use that feature with Zig?

2

Figured this out! You can use emit-llvm-ir to get an .ll file with textual IR:

        if (options.emit_llvm_ir) {
            steps.install.dependOn(&b.addInstallBinFile(
                tigerbeetle_exe.getEmittedLlvmIr(),
                "tigerbeetle.ll",
            ).step);
        }

Then, you can feed that file to llc which accepts all the LLVM options:

 /opt/homebrew/opt/llvm/bin/llc zig-out/bin/tigerbeetle.ll --stack-size-section -non-global-value-max-name-size=65536

That produces an .s file which you still need to compile somehow, but I was able to get the stack size info from the textual file just fine.

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