[inline asm] .stabs directive support

[llvmbot]

Bugzilla Link	31134
Version	unspecified
OS	Windows NT
Blocks	#4440
Reporter	LLVM Bugzilla Contributor
CC	@compnerd,@efriedma-quic,@nickdesaulniers,@paulmenzel

Extended Description

There is no support for the .stabs directive

[compnerd]

LLVM currently has no STABS debugging format support. Im not sure that adding the assembler support for it is useful until such time as it can generate the STABS debug info.

That said, DWARF has almost entirely replaced STABS for debugging. Im not sure that we really want a third debugging format, especially when STABS is officially deprecated in favor of DWARF.

[paulmenzel]

This also affects the Linux kernel 1.

[efriedma-quic]

I assume the Linux kernel's usage of .stabs is leftover junk, not actually intentional usage. I'm sure they'd be happy to take a patch to remove the directives.

[paulmenzel]

I assume the Linux kernel's usage of .stabs is leftover junk, not actually
intentional usage. I'm sure they'd be happy to take a patch to remove the
directives.

I am going to inform the Linux kernel maintainers about the problem, but not supporting this in Clang means that older Linux kernels and probably other programs too, can’t be successfully compiled with Clang.

[edwintorok]

mentioned in issue #4440