creating static libraries targeting macosx results in unusable .a files

[andrewrk]

export fn foo() void {}

zig build-lib foo.zig

void foo(void);
int main() {foo(); return 0;}

cc -o test test.c foo.a
ld: warning: ignoring file foo.a, file was built for archive which is not the architecture being linked (x86_64): foo.a

The error message is bogus; the file is of course the correct architecture.

Suggestion here is to use libtool -static -o libio.a io.o rather than ar.:
https://stackoverflow.com/questions/30948807/static-library-link-issue-with-mac-os-x-symbols-not-found-for-architecture-x8

We will have to figure out how to do that using LLVM API.

A workaround for this bug is to use build-obj instead of build-lib. Indeed that's the workaround here:

zig/src/link.cpp

Lines 35 to 42 in 74a335c

	// The Mach-O LLD code is not well maintained, and trips an assertion
	// when we link compiler_rt and builtin as libraries rather than objects.
	// Here we workaround this by having compiler_rt and builtin be objects.
	// TODO write our own linker. https://github.com/ziglang/zig/issues/1535
	OutType child_out_type = OutTypeLib;
	if (parent_gen->zig_target.os == OsMacOSX) {
	child_out_type = OutTypeObj;
	}

Related issue regarding a new linker: #1535
Related issue regarding dynamic libraries: #1982

[LemonBoy]

// The Mach-O LLD code is not well maintained, and trips an assertion
// when we link compiler_rt and builtin as libraries rather than objects.

Is the assertion you get the same as #2421?

[andrewrk]

I believe I was tripping

zig/deps/lld/lib/ReaderWriter/MachO/ArchHandler_x86_64.cpp

Line 442 in 1c73c08

llvm_unreachable("bad reloc kind");

and some of the other equivalent assertions in this file.