[musl] Re: Bug#1068350: musl: miscompiles (runtime problems) on riscv64 and s390x with static-pie → seems to be a toolchain bug after all, it does too hit glibc

[Thorsten Glaser <tg@mirbsd.de>]

Dixi quod…

>Now I (or someone) is going to have to reduce that to a testcase, so

No success with that, unfortunately.

>But this does seem to be a toolchain bug: adding -static-pie to the
>glibc dynamic-pie link command and…
>
>(gdb) print initcoms
>$1 = {0xda494 "typeset", 0x0, 0x0, 0x0, 0xda494 "typeset", 0x0, 0xd942c "HOME", 0xda7d8 "PATH",

Wait, what?

(gdb) b main
Breakpoint 1 at 0xd820: file ../../main.c, line 785.
(gdb) print initcoms
$1 = {0xda494 "typeset", 0x0, 0x0, 0x0, 0xda494 "typeset", 0x0, 0xd942c "HOME", 0xda7d8 "PATH",
[…]
(gdb) r
Starting program: /home/tg/mksh-59c/builddir/full/mksh

Breakpoint 1, main (argc=1, argv=0x3ffffffa4d8) at ../../main.c:785
785     {
(gdb) print initcoms
$2 = {0x3fff7eda494 "typeset", 0x3fff7ee4548 <u_ops+128> "-r",
  0x3fff7ee4ae0 <initvsn> "KSH_VERSION=@(#)MIRBSD KSH R59 2024/02/01 +Debian", 0x0, 0x3fff7eda494 "typeset",
[…]

While in musl:

(gdb) print initcoms
$1 = {0x414a4 "typeset", 0x0, 0x0, 0x0, 0x414a4 "typeset", 0x0, 0x40478 "HOME", 0x41d42 "PATH",
[…]
(gdb) r
Starting program: /home/tg/mksh-59c/builddir/static-musl/mksh

Breakpoint 1, main (argc=1, argv=0x3ffffffa498) at ../../main.c:785
785     {
(gdb) print initcoms
$2 = {0x3fff7fc14a4 "typeset", 0x0, 0x0, 0x0, 0x3fff7fc14a4 "typeset", 0x0, 0x3fff7fc0478 "HOME",
[…]

So the existing ones did get relocated, but the nullptrs stayed thusly.

Apparently, it *is* supported on glibc on s390x, mjt (qemu maintainer)
also said so in 2023.

bye,
//mirabilos
-- 
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