From 14e56bd4ce15ac2d1cc43f762eb2e6b83fec1afe Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Sun, 14 Apr 2024 08:24:51 +0200 Subject: [PATCH] powerpc: Fix ld.so address determination for PCREL mode (bug 31640) This seems to have stopped working with some GCC 14 versions, which clobber r2. With other compilers, the kernel-provided r2 value is still available at this point. Reviewed-by: Peter Bergner --- sysdeps/powerpc/powerpc64/dl-machine.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/sysdeps/powerpc/powerpc64/dl-machine.h b/sysdeps/powerpc/powerpc64/dl-machine.h index c6682f3445..2b6f5d2b08 100644 --- a/sysdeps/powerpc/powerpc64/dl-machine.h +++ b/sysdeps/powerpc/powerpc64/dl-machine.h @@ -78,6 +78,7 @@ elf_host_tolerates_class (const Elf64_Ehdr *ehdr) static inline Elf64_Addr elf_machine_load_address (void) __attribute__ ((const)); +#ifndef __PCREL__ static inline Elf64_Addr elf_machine_load_address (void) { @@ -105,6 +106,24 @@ elf_machine_dynamic (void) /* Then subtract off the load address offset. */ return runtime_dynamic - elf_machine_load_address() ; } +#else /* __PCREL__ */ +/* In PCREL mode, r2 may have been clobbered. Rely on relative + relocations instead. */ + +static inline ElfW(Addr) +elf_machine_load_address (void) +{ + extern const ElfW(Ehdr) __ehdr_start attribute_hidden; + return (ElfW(Addr)) &__ehdr_start; +} + +static inline ElfW(Addr) +elf_machine_dynamic (void) +{ + extern ElfW(Dyn) _DYNAMIC[] attribute_hidden; + return (ElfW(Addr)) _DYNAMIC - elf_machine_load_address (); +} +#endif /* __PCREL__ */ /* The PLT uses Elf64_Rela relocs. */ #define elf_machine_relplt elf_machine_rela