The spec says:
If a symbol definition with STV_PROTECTED visibility from a shared
object is taken as resolving a reference from an executable or another
shared object, the SHN_UNDEF symbol table entry created has STV_DEFAULT
visibility.
llvm-svn: 265792
This patch fixes dynamic relocation creation from GOT access in dynamic
objects on aarch64. Current code creates a plt relative one
(R_AARCH64_JUMP_SLOT) instead of a got relative (R_AARCH64_GLOB_DAT).
It leads the programs fails with:
$ cat t.cc
std::string test = "hello...\n";
int main ()
{
printf ("%s\n", test.c_str());
return 0;
}
$ clang++ t.cc -fpic -o t
$ ./t
hello...
Segmentation fault (core dumped)
Due the fact it will try to access the plt instead of the got for
__cxa_atexit registration for the std::string destruction. It will
lead in a bogus function address in atexit.
llvm-svn: 265784
Previously, we supported only one hash function, FNV-1, so
BuildIdSection directly handled hash computation. In this patch,
I made BuildIdSection an abstract class and defined two subclasses,
BuildIdFnv1 and BuildIdMd5.
llvm-svn: 265737
start-lib and end-lib are options to link object files in the same
semantics as archive files. If an object is in start-lib and end-lib,
the object is linked only when the file is needed to resolve
undefined symbols. That means, if an object is in start-lib and end-lib,
it behaves as if it were in an archive file.
In this patch, I introduced a new notion, LazyObjectFile. That is
analogous to Archive file type, but that works for a single object
file instead of for an archive file.
http://reviews.llvm.org/D18814
llvm-svn: 265710
This requires knowing input section offsets in output sections before
scanRelocs. This is generally a good thing and should allow further
simplifications in the creation of dynamic relocations.
llvm-svn: 265673
Stack is not executable by default in LLD-built executables unless
you pass -z execstack option. So --warn-execstack option does not make
sense to us.
llvm-svn: 265619
With the llvm change in r265606 this is the matching needed change to the lld
code now that createBinary() is returning Expected<...> .
llvm-svn: 265607
This patch add a base script tokenizer class to decouple parsing from
linker script handling. The idea is to use this base class on dynamic
list parsing (--dynamic-list option). No functionality added.
llvm-svn: 265600
Similar to r265462, TLS related relocations aren't marked as relative,
meaning that we end up generating R_AARCH64_RELATIVE relocations for
them. This change adds TLS relocations that I've seen on my system. With
this patch applied CloudABI's unit testing binary now passes on aarch64.
Approved by: ruiu
Differential Revision: http://reviews.llvm.org/D18816
llvm-svn: 265575
We have to differentiate undefined symbols from bitcode and undefined
symbols from other sources.
Undefined symbols from bitcode should not inhibit the symbol being
internalized. Undefined symbols from other sources should.
llvm-svn: 265536
When error, this adds the text line of script to the output
and a marks exact incorrect token under it:
line 1: <error text here>
UNKNOWN_TAG {
^
Differential revision: http://reviews.llvm.org/D18699
llvm-svn: 265523
ELF and program header are not part of OutputSections list anymore.
That helps to avoid having and working with functions like dummySectionsNum().
Still keeping them as sections helps to simplify the code.
Differential revision: http://reviews.llvm.org/D18743
llvm-svn: 265522
Summary:
This bug was introduced by http://reviews.llvm.org/rL265059,
where InputSectionBase got Thunks field, which can do memory allocations.
Since InputSectionBase destructors were never called (I count it as another bug),
that caused a memory leak when 2 or more thunks are added to a section.
The fix to is properly call InputSectionBase destructors from ~ObjectFile.
Reviewers: atanasyan, ruiu, rafael
Subscribers: rafael, krasin, pcc
Differential Revision: http://reviews.llvm.org/D18809
llvm-svn: 265497
While trying to get PIE work on CloudABI for x86-64, I noticed that even
though GNU ld would generate functional binaries, LLD would not. It
turns out that we generate relocations for referencing TLS objects
inside of the text segment, which shouldn't happen.
This change extends the isRelRelative() function to list some additional
relocation types that should be treated as relative. This makes my C
library unit testing binary work on x86-64.
Approved by: ruiu
Differential Revision: http://reviews.llvm.org/D18688
Fixes bug: https://llvm.org/bugs/show_bug.cgi?id=27174
llvm-svn: 265462
Where Clang's AArch64 backend seems to differ from the X86 backend is
that it tends to use the GOT more aggressively.
After getting CloudABI PIEs working on x86-64, I noticed that accessing
global variables would still crash on aarch64. Tracing it down, it turns
out that the GOT was filled with entries assuming the base address was
zero.
It turns out that we skip generating relocations for GOT entries in case
the relocation pointing towards the GOT is relative. Whether the thing
pointing to the GOT is absolute or relative shouldn't make any
difference; the GOT entry itself should contain the absolute address,
thus needs a relocation regardless.
Approved by: rafael
Differential Revision: http://reviews.llvm.org/D18739
llvm-svn: 265453
Make sure to copy the MustBeInDynSym field when replacing shared symbols with
bitcode symbols, and when replacing bitcode symbols with regular symbols
in addCombinedLtoObject. Fixes interposition of DSO symbols with bitcode
symbols in the main executable.
Differential Revision: http://reviews.llvm.org/D18780
llvm-svn: 265371
For each copy relocation that we create, look through the DSO's symbol table
for aliases and create a dynamic symbol for each one. This causes the copy
relocation to correctly interpose any aliases.
Copy relocations are relatively uncommon (on my machine, 56% of binaries in
/usr/bin have no copy relocations probably due to being PIEs, 97% of them
have <10, and the binary with the largest number of them has 97) so it's
probably fine to do this in a relatively inefficient way.
Differential Revision: http://reviews.llvm.org/D18731
llvm-svn: 265354
Rafael Espindola