This causes errors like:
ld: error: blah.o: requires dynamic R_X86_64_PC32 reloc against '' which
may overflow at runtime; recompile with -fPIC
blah.cc:function f(): error: undefined reference to ''
blah.o:g(): error: undefined reference to ''
I have not yet come up with an appropriate reproduction.
llvm-svn: 240394
Now that pr23900 is fixed, we can bring it back with no changes.
Original message:
Make all temporary symbols unnamed.
What this does is make all symbols that would otherwise start with a .L
(or L on MachO) unnamed.
Some of these symbols still show up in the symbol table, but we can just
make them unnamed.
In order to make sure we produce identical results when going thought assembly,
all .L (not just the compiler produced ones), are now unnamed.
Running llc on llvm-as.opt.bc, the peak memory usage goes from 208.24MB to
205.57MB.
llvm-svn: 240302
What this does is make all symbols that would otherwise start with a .L
(or L on MachO) unnamed.
Some of these symbols still show up in the symbol table, but we can just
make them unnamed.
In order to make sure we produce identical results when going thought assembly,
all .L (not just the compiler produced ones), are now unnamed.
Running llc on llvm-as.opt.bc, the peak memory usage goes from 208.24MB to
205.57MB.
llvm-svn: 240130
Section symbols exist as an optimization: instead of having multiple relocations
point to different symbols, many of them can point to a single section symbol.
When that optimization is unused, a section symbol is also unused and adds no
extra information to the object file.
This saves a bit of space on the object files and makes the output of
llvm-objdump -t easier to read and consequently some tests get quite a bit
simpler.
llvm-svn: 239045
The ELF spec is very clear:
-----------------------------------------------------------------------------
If the value is non-zero, it represents a string table index that gives the
symbol name. Otherwise, the symbol table entry has no name.
--------------------------------------------------------------------------
In particular, a st_name of 0 most certainly doesn't mean that the symbol has
the same name as the section.
llvm-svn: 238899
The symbol table itself has no relocations, so it is not possible to represent
things like
a = undefined + 1
With the patch we just omit these variables. That matches the behaviour of the
gnu assembler.
llvm-svn: 207419
just
.type foo,@object
will produce an undefined reference to foo. On the other hand, a file with
just
.weakref bar, foo
will not. It is somewhat hard to support both in MC since both statements
should create the symbols. It should be possible if we really need to by
adding to the flags, but hopefully that is not necessary.
With this patch we do not produce a undefined reference in any of those cases.
The assembly file needs an actual use for the undefined reference to be
present.
This is in preparation for a patch implementing .weakref.
llvm-svn: 117735
The failures in r116753 r116756 were caused by a python issue -
Python likes to append 'L' suffix to stringified numbers if the number
is larger than a machine int. Unfortunately, this causes a divergence of
behavior between 32 and 64 bit python versions.
I re-crafted elf-dump/common_dump to take care of these issues by:
1. always printing 0x (makes for easy sed/regex)
2. always print fixed length (exactly 2 + numBits/4 digits long)
by mod ((2^numBits) - 1)
3. left-padded with '0'
There is a residual common routine that is also used by
macho-dump (dataToHex) , so I left the 'section_data' test values alone.
llvm-svn: 116823
