forked from OSchip/llvm-project
aa1f2c50a8
GNU objcopy uses bfd_elf_get_default_section_type to decide the candidate section type,
which roughly translates to our [a] (I assume SEC_COMMON implies SHF_ALLOC):
(!(Sec.Flags & ELF::SHF_ALLOC) || Flags & (SectionFlag::SecContents | SectionFlag::SecLoad)))
Then, it updates the section type in bfd/elf.c:elf_fake_sections if:
if (this_hdr->sh_type == SHT_NULL)
this_hdr->sh_type = sh_type; // common case
else if (this_hdr->sh_type == SHT_NOBITS
&& sh_type == SHT_PROGBITS
&& (asect->flags & SEC_ALLOC) != 0) // uncommon case
...
this_hdr->sh_type = sh_type;
If the following condition is met the uncommon branch is executed:
if (elf_section_type (osec) == SHT_NULL
&& (osec->flags == isec->flags
|| (final_link
&& ((osec->flags ^ isec->flags)
& ~(SEC_LINK_ONCE | SEC_LINK_DUPLICATES | SEC_RELOC)) == 0)))
I suggest we just ignore this clause and follow the common case
behavior, which is done in this patch. Rationales to do so:
If --set-section-flags is a no-op (osec->flags == isec->flags)
(corresponds to the "readonly" test in set-section-flags.test), GNU
objcopy will require (Sec.Flags & ELF::SHF_ALLOC). [a] is essentially:
Flags & (SectionFlag::SecContents | SectionFlag::SecLoad)
This special case is not really useful. Non-SHF_ALLOC SHT_NOBITS
sections do not make much sense and it doesn't matter if they are
SHT_NOBITS or SHT_PROGBITS.
For all other RUN lines in set-section-flags.test, the new behavior
matches GNU objcopy, i.e. this patch improves compatibility.
Differential Revision: https://reviews.llvm.org/D60189
llvm-svn: 359639
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| .. | ||
| dsymutil | ||
| gold | ||
| llvm-ar | ||
| llvm-cfi-verify | ||
| llvm-config | ||
| llvm-cov | ||
| llvm-cvtres | ||
| llvm-cxxdump | ||
| llvm-cxxfilt | ||
| llvm-cxxmap | ||
| llvm-diff | ||
| llvm-dlltool | ||
| llvm-dwarfdump | ||
| llvm-dwp | ||
| llvm-elfabi | ||
| llvm-exegesis | ||
| llvm-extract | ||
| llvm-isel-fuzzer | ||
| llvm-lib | ||
| llvm-lit | ||
| llvm-lto | ||
| llvm-lto2 | ||
| llvm-mc | ||
| llvm-mca | ||
| llvm-modextract | ||
| llvm-mt | ||
| llvm-nm | ||
| llvm-objcopy | ||
| llvm-objdump | ||
| llvm-opt-fuzzer | ||
| llvm-opt-report | ||
| llvm-pdbdump | ||
| llvm-profdata | ||
| llvm-rc | ||
| llvm-readobj | ||
| llvm-size | ||
| llvm-split | ||
| llvm-strings | ||
| llvm-symbolizer | ||
| llvm-xray/X86 | ||
| lto | ||
| obj2yaml | ||
| opt-viewer | ||
| sancov | ||
| sanstats | ||
| yaml2obj | ||