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From: "i at maskray dot me" <sourceware-bugzilla@sourceware.org>
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Subject: [Bug dynamic-link/29071] m68k: Removal of ELF_DURING_STARTUP
 optimization broke ld.so
Date: Mon, 18 Apr 2022 15:57:25 +0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=3D29071

--- Comment #9 from Fangrui Song <i at maskray dot me> ---
Unrolling this may mitigate the issue likely because the optimization is
related to loop-invariant code motion. gcc somehow decides hoisting the GOT
address of the jump table is beneficial (for such a non-PI_STATIC_AND_HIDDEN
arch).

musl ld.so uses a function call as a barrier (__dls2) to avoid such code
generation problems.

(In reply to Andreas Schwab from comment #8)
> Created attachment 14070 [details]
> handle less relocation types during ld.so bootstrap
>=20
> Please try this instead.

Thanks. This looks good to me. `case R_68K_NONE` can also be placed in `#if=
def
RTLD_BOOTSTRAP` if it helps reduce the possibility that gcc uses a jump tab=
le
(which needs a relocated address in a GOT entry).

--=20
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