binutils-gdb/ld/testsuite/ld-mips-elf/reloc-local-overflow.s

	.data
	.space	0x1000

	.align	2
	.type	bar, @object
bar:
	.half	bar
	.size	bar, . - bar
MIPS/BFD: Fix section symbol name fetching in relocation Symbol table entries for section symbols are different between IRIX and traditional MIPS ELF targets in that IRIX entries have their `st_name' member pointing at the section's name in the string table section, while traditional entries have 0 there and the section header string table has to be referred via the relevant section header's `shn_name' member instead. This is chosen with the `elf_backend_name_local_section_symbols' backend and can be observed with `readelf -s' output for an IRIX object: Symbol table '.symtab' contains 12 entries: Num: Value Size Type Bind Vis Ndx Name 0: 00000000 0 NOTYPE LOCAL DEFAULT UND 1: 00000000 0 SECTION LOCAL DEFAULT 1 .text 2: 00000000 0 SECTION LOCAL DEFAULT 3 .data 3: 00000000 0 SECTION LOCAL DEFAULT 4 .bss 4: 00000000 0 SECTION LOCAL DEFAULT 5 .reginfo 5: 00000000 0 SECTION LOCAL DEFAULT 6 .MIPS.abiflags 6: 00000000 0 SECTION LOCAL DEFAULT 7 .pdr 7: 00000000 0 SECTION LOCAL DEFAULT 9 .gnu.attributes 8: 00002000 16 FUNC GLOBAL DEFAULT 1 foo 9: 00004008 0 FUNC LOCAL DEFAULT 1 abar 10: 00002008 0 FUNC LOCAL DEFAULT 1 afoo 11: 00004000 16 FUNC GLOBAL DEFAULT 1 bar and a corresponding traditional object: Symbol table '.symtab' contains 12 entries: Num: Value Size Type Bind Vis Ndx Name 0: 00000000 0 NOTYPE LOCAL DEFAULT UND 1: 00000000 0 SECTION LOCAL DEFAULT 1 2: 00000000 0 SECTION LOCAL DEFAULT 3 3: 00000000 0 SECTION LOCAL DEFAULT 4 4: 00004008 0 FUNC LOCAL DEFAULT 1 abar 5: 00002008 0 FUNC LOCAL DEFAULT 1 afoo 6: 00000000 0 SECTION LOCAL DEFAULT 5 7: 00000000 0 SECTION LOCAL DEFAULT 6 8: 00000000 0 SECTION LOCAL DEFAULT 7 9: 00000000 0 SECTION LOCAL DEFAULT 9 10: 00002000 16 FUNC GLOBAL DEFAULT 1 foo 11: 00004000 16 FUNC GLOBAL DEFAULT 1 bar respectively. Consequently the right way to retrieve a section symbol's name has to be chosen in `mips_elf_calculate_relocation' for the purpose of error reporting. Originally we produced symbol tables in the traditional object format only and we handled it correctly until it was lost in a rewrite with: commit 7403cb6305f5660fccc8869d3333a731102ae978 Author: Mark Mitchell <mark@codesourcery.com> Date: Wed Jun 30 20:13:43 1999 +0000 probably because of the extra pointer indirection added which made the same expression have a different meaning. With the addition of IRIX symbol table format with: commit 174fd7f9556183397625dbfa99ef68ecd325c74b Author: Richard Sandiford <rdsandiford@googlemail.com> Date: Mon Feb 9 08:04:00 2004 +0000 the bug has been partially covered and now when a relocation error is triggered with an IRIX object the offending section symbol is correctly reported: tmpdir/dump0.o: In function `foo': (.text+0x2000): relocation truncated to fit: R_MIPS_26 against `.text' tmpdir/dump0.o: In function `bar': (.text+0x4000): relocation truncated to fit: R_MIPS_26 against `.text' because `bfd_elf_string_from_elf_section' retrieves the name from the string table section. With a traditional object however the function returns an empty string and consequently `no symbol' is printed instead: tmpdir/dump0.o: In function `foo': (.text+0x2000): relocation truncated to fit: R_MIPS_26 against `no symbol' tmpdir/dump0.o: In function `bar': (.text+0x4000): relocation truncated to fit: R_MIPS_26 against `no symbol' Restore the original semantics so that the section name is always correctly retrieved. bfd/ * elfxx-mips.c (mips_elf_calculate_relocation): Also use the section name if `bfd_elf_string_from_elf_section' returns an empty string. ld/ * testsuite/ld-mips-elf/reloc-local-overflow.d: New test. * testsuite/ld-mips-elf/reloc-local-overflow.s: Source for the new test. * testsuite/ld-mips-elf/mips-elf.exp: Run the new test. 2016-05-28 03:41:40 +08:00			`.data`
			`.space 0x1000`

			`.align 2`
			`.type bar, @object`
			`bar:`
			`.half bar`
			`.size bar, . - bar`