Re: GDB 17 build failure with musl

[Thiago Jung Bauermann via Gdb <gdb@sourceware.org>]

Chris Packham <judge.packham@gmail.com> writes:

> On Tue, Feb 3, 2026 at 4:10 PM Thiago Jung Bauermann
> <thiago.bauermann@linaro.org> wrote:
>>
>> Do you have reproduction instructions for this problem? I'd like to
>> experiment a bit and see if I can come up with a solution.
>
> The only reproduction I have right now is to build crosstool-ng then
> use ct-ng to build the aarch64-unknown-linux-musl sample. You'd need
> to build from crosstool-ng commit be7fafbc7b6435 as I ended up
> reverting the update for now to unblock some builds.
>
> For the intrepid:
>
>   git clone https://github.com/crosstool-ng/crosstool-ng.git
>   cd crosstool-ng
>   git checkout -B gdb-17-build  be7fafbc7b6435
>   ./bootstrap && ./configure --enable-local && make
>   ./ct-ng aarch64-unknown-linux-musl
>   ./ct-ng build
>   # go get a coffee this part can take a while
>
> I have been meaning to come up with a better reproduction. At the very
> least you could disable the gdb options in ./ct-ng menuconfig and use
> the resulting toolchain & sysroot to build gdb rather than having to
> sit through a full build to try something out (ct-ng does also have
> various options for restarting a build from a particular step).

Thank you! This got me started. I suspect I'll have to add a configure
test for availability of struct user_gcs. I don't see any macro in
<asm/ptrace.h> itself which is correlated to the presence of that
struct. I'll let you know when I have a patch.


> I actually suspect you could probably see the problem on a musl based
> distro on an aarch64 host (or docker multiarch) but I haven't looked
> into that.

Ah, that's true. I'll also test on Alpine Linux to make sure the patch
works there.

-- 
Thiago