https://sourceware.org/bugzilla/show_bug.cgi?id=21233
--- Comment #9 from Maciej W. Rozycki <ma...@linux-mips.org> --- Created attachment 9925 --> https://sourceware.org/bugzilla/attachment.cgi?id=9925&action=edit WIP bug fix This is indeed another incorrectly handled scenario that would have qualified under PR ld/20828. Here we have a symbol which has been forced local, however it has retained its GGA_NORMAL GOT assignment. Consequently it is considered external by the MIPS backend and assigned to the global part of both GOT and the dynamic symbol table. However the generic ELF linker has already included it in the local symbol count and as a result a mismatch happens in the MIPS backend between the number of symbols expected and actually assigned to the non-GOT-mapped and GOT-mapped parts of the dynamic symbol table, which is caught by the: BFD_ASSERT (hsd.max_non_got_dynindx <= hsd.min_got_dynindx) assertion, saving the linker's skin as with this assertion removed a broken binary (with the offending symbol missing due to a wrong dynamic symbol index assignment) would be produced: Symbol table '.dynsym' contains 10 entries: Num: Value Size Type Bind Vis Ndx Name 0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND 1: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND 2: 00000001200104f0 0 NOTYPE GLOBAL DEFAULT 7 _fdata 3: 0000000000000001 0 SECTION GLOBAL DEFAULT ABS _DYNAMIC_LINKING 4: 00000001200004db 0 NOTYPE GLOBAL DEFAULT 6 _ftext 5: 00000001200104f0 0 OBJECT GLOBAL DEFAULT 7 __RLD_MAP 6: 0000000120010518 0 NOTYPE GLOBAL DEFAULT 8 __bss_start 7: 0000000120010518 0 NOTYPE GLOBAL DEFAULT 8 _edata 8: 0000000120010518 0 NOTYPE GLOBAL DEFAULT 8 _end 9: 0000000120010518 0 NOTYPE GLOBAL DEFAULT 8 _fbss -- notice the bad entry at 1, where `alpha' should be if considered local. Here is another similarity though to what has already been covered in PR ld/20828 in that I think with `alpha' chosen with `-u' (or, for that matter `--require-defined') or the equivalent EXTERN linker script command the symbol shouldn't have been garbage-collected in the first place, as this defeats the purpose of these constructs. So I believe that by these contstructs' definition symbols thus created have to be retained and therefore remain external. That has led me to the patch proposed, which obviously fixes James's reduced test case. Unfortunately I am unable to reproduce the libgomp's configuration failure and trying to build ghc is out of question too, so I do not know if they are cases of `-u'/`--require-defined'/EXTERN or maybe there is yet another way for forced local GGA_NORMAL symbols to make it through linking. So, Gianfranco and Alastair, would you please try the patch proposed and see if it fixes the issue for you? If so, then I'll proceed with creating suitable linker test suite cases and following the usual procedure to apply the fix to binutils sources, or at least trunk where it also triggers. For 2.28, like with PR ld/20828, I may instead choose to limit the solution to the MIPS backend, and only use a workaround where forced local symbols are made GGA_NONE, which I'm leaning towards doing anyway. -- You are receiving this mail because: You are on the CC list for the bug. _______________________________________________ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
