Re: [musl] [PATCH] arm64: uapi: Fix user space compile with musl libc

On 10/19/19 10:29 PM, Rich Felker wrote:

On Sat, Oct 19, 2019 at 10:17:17PM +0200, Hauke Mehrtens wrote:

quoted

musl libc also defines the structures in their arch/aarch64/bits/signal.h
header file. Some applications like strace and gdb include both of them
and then the structure definitions are clashing and the build of these
user space applications fails.

This patch allows a libc to define a constant which tells the kernel
header file that the libc already defined these structures and that they
should not be defined by the kernel uapi header files any more to
prevent clashes. This is done in a similar way as it is already done for
other header files.

When this patch was accepted into the kernel I will also update musl
libc to define these constants.

I don't entirely object to this outright, but I'd really like to avoid
adding further __UAPI_DEF_* suppressions. AIUI asm/sigcontext.h is not
intended to be used with userspace headers. Is it still being
indirectly included via some other uapi headers? (I thought that was
fixed..) If so, that should really be fixed first, and then we can see
if there's still motivation for the patch here.

Rich

Hi Rich,

I did some more research and it looks like this patch also fixes my
problem with strace and gdb compile:
https://git.kernel.org/linus/9966a05c7b80f075f2bc7e48dbb108d3f2927234

I will backport it in OpenWrt to kernel 4.19.

Please drop my patch.

It would be nice if it could go into the stable 4.19 kernel.

Hauke