This change lets MSan rely on libcxx's own build system instead of manually
compiling its sources and setting up all the necessary compile flags. It would
also simplify compiling libcxx with another sanitizers (in particular, TSan).
The tricky part is to make sure libcxx is reconfigured/rebuilt when Clang or
MSan runtime library is changed. "clobber" step used in this patch works well
for me, but it's possible it would break for other configurations - will
watch the buildbots.
llvm-svn: 208451
Summary:
The loader does not call mmap() through the PLT because it has to
bootstrap the process before libc is present. Hooking dlopen() isn't
enough either because the loader runs module initializers before
returning, and they could run arbitrary msan instrumented code.
If msandr is present, then we can intercept the mmaps from dlopen at the
syscall layer and clear the shadow there. If msandr is missing, we
clear the shadow after dlopen() and hope any initializers are trivial.
Reviewers: eugenis
CC: kcc, llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D509
llvm-svn: 176818
Build system setup for MSan lit tests (build with freshly-built clang, run,
check output) - a nearly exact copy from ASan.
First 2 lit tests for MSan.
llvm-svn: 174876
Moved everything users are not supposed to use to a private interface header.
Documented all public interfaces. Made them safe to use even if built without
MemorySanitizer.
llvm-svn: 173800
Alexey Samsonov