This adds support for reading the "bigobj" variant of COFF produced by
cl's /bigobj and mingw's -mbig-obj.
The most significant difference that bigobj brings is more than 2**16
sections to COFF.
bigobj brings a few interesting differences with it:
- It doesn't have a Characteristics field in the file header.
- It doesn't have a SizeOfOptionalHeader field in the file header (it's
only used in executable files).
- Auxiliary symbol records have the same width as a symbol table entry.
Since symbol table entries are bigger, so are auxiliary symbol
records.
Write support will come soon.
Differential Revision: http://reviews.llvm.org/D5259
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217496 91177308-0d34-0410-b5e6-96231b3b80d8
MC was aping a binutils bug where aliases would default their linkage to
private instead of internal.
I've sent a patch to the binutils maintainers and they've recently
applied it to the GNU assembler sources.
This fixes PR20152.
Differential Revision: http://reviews.llvm.org/D4395
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212899 91177308-0d34-0410-b5e6-96231b3b80d8
Prevent the early elimination of sections in the object writer. There may be
references to the section itself by other symbols, which may potentially not be
possible to resolve. ML (Visual Studio's Macro Assembler) also seems to retain
empty sections.
The elimination of symbols and sections which are unused should really occur at
the link phase. This will not cause any change in the resulting binary, simply
in the generated object files.
The adjustments to the other unit tests account for the fluctuating section
index caused by the appearance of sections which were previously discarded.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210373 91177308-0d34-0410-b5e6-96231b3b80d8
This matches gas' behaviour on COFF.
I think that this yak is now sufficiently shaved for aliases with offset
to work.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207786 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r190888, to fix PR17967. The original change wasn't
the right way to get @feat.00 into the object file. The right fix is to
make @feat.00 be a global symbol.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195053 91177308-0d34-0410-b5e6-96231b3b80d8
In particular, this means we emit non-external symbols defined to
variables, such as aliases or absolute addresses.
This is needed to implement /safeseh, and it appears there was some
confusion about what symbols to emit previously.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190888 91177308-0d34-0410-b5e6-96231b3b80d8
