[Bug compile/34551] Summary: compile command: external calls from compiled modules crash on powerpc64le

https://sourceware.org/bugzilla/show_bug.cgi?id=34551

--- Comment #2 from Sourceware Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Abhay Kandpal <[email protected]>:

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a6d0eb39462588ed757cb1fe97749863604588ff

commit a6d0eb39462588ed757cb1fe97749863604588ff
Author: Abhay Kandpal <[email protected]>
Date:   Thu Aug 20 07:03:57 2026 -0500

    PowerPC: fix external calls from modules built by the compile command

    A module built for the compile command is loaded into inferior memory
    without a linker, so it has no PLT.  On ELFv2 the default code model
    still emits a direct bl for a call to another module, leaving r12 unset
    and the caller's TOC pointer unrestored, and the callee then derives a
    wrong r2 from a stale r12.

    gdb.compile/compile-setjmp.exp shows this: the injected code calls
    setjmp, whose global entry point computes r2 from a stale r12, and the
    first TOC-relative load segfaults.

    -mlongcall makes the call indirect, but on its own it reaches the target
    through a PLT entry, giving R_PPC64_PLT16_HA/LO_DS relocations that BFD's
    generic linker rejects.  Adding -mno-pltseq resolves the call against the
    module's own TOC instead, via R_PPC64_TOC16_HA/LO_DS, which GDB already
    handles.  GCC then emits the r2 save and restore around the call itself.

    Tested on powerpc64le-linux; the two compile-setjmp.exp failures now pass
    with no unexpected failures in the full testsuite.

    gdb/
            * ppc-linux-tdep.c (ppc64_gcc_target_options): New function.
            (ppc_linux_init_abi): Set gcc_target_options for ELFv2.

    Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=34551
    Suggested-by: Ulrich Weigand <[email protected]>

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