Shared objects are hard. After this commit, we do the right thing when
profiling two separate shared objects that have been dlopen'd with
`RTLD_LOCAL`, when the main executable is *not* being profiled.
This mainly simplifies the writer logic.
- At initialization, determine the output filename and truncate the
file. Depending on whether shared objects can see each other, this
may happen multiple times.
- At exit, each executable writes its own profile in append mode.
<rdar://problem/16918688>
llvm-svn: 209053
These tests were XPASS-ing on Linux bots creating Mach-O, which makes
sense, since the real difference is the object format.
I'm hoping a short-term fix to get these tests passing on ELF is to
create two copies of the runtime -- one built with -fPIC, and one
without. A follow-up patch will change clang's driver to pick between
them depending on whether `-shared` is specified.
llvm-svn: 208947
According to the buildbots, the new features for shared objects don't
work on ELF since it requires an -fPIC when building the profile
library. XFAIL these tests for now.
It's possible we'll have to build two versions of the profile library on
Linux (one with -fPIC and one without), but it's not clear to me exactly
how to resolve this.
llvm-svn: 208946
Change the API of the instrumented profiling library to work with shared
objects.
- Most things are now declared hidden, so that each executable gets
its own copy.
- Initialization hooks up a linked list of writers.
- The raw format with shared objects that are profiled consists of a
concatenated series of profiles. llvm-profdata knows how to deal
with that since r208938.
<rdar://problem/16918688>
llvm-svn: 208940
for sanitizers to pass the C++ compilation and exe linking flags through
from the host CMake configuration. We pass the target flags afterward,
allowing them to trump flags as needed. This is particularly important
when the flags direct Clang, even the just-built-Clang, toward the
standard library, linker, and other tools to use.
llvm-svn: 208896
User-visible instances of xdr_ops always seem to be allocated statically, and
don't need unpoisoning. Also, it's size differs between platforms.
llvm-svn: 208851
TSan can produce false positives in code that uses C++11 threading,
as it doesn't see synchronization inside standard library. See
http://lists.cs.uiuc.edu/pipermail/cfe-dev/2014-February/035408.html
for an example of such case.
We may build custom TSan-instrumented version libcxx to fight with that.
This change adds build rules for libcxx_tsan and integrates it into
testing infrastructure.
llvm-svn: 208737
Duncan P. N. Exon Smith