PR15383: When -fsanitize=float-cast-overflow checks a float-to-int conversion,
it wasn't taking into account that the float should be truncated *before* the
range check happens. Thus (unsigned)-0.99 and (unsigned char)255.9 have defined
behavior and should not be trapped.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177362 91177308-0d34-0410-b5e6-96231b3b80d8
<rdar://problem/13363214> Eliminate race condition between module rebuild and the global module index.

The global module index was querying the file manager for each of the
module files it knows about at load time, to prune out any out-of-date
information. The file manager would then cache the results of the
stat() falls used to find that module file.

Later, the same translation unit could end up trying to import one of the
module files that had previously been ignored by the module cache, but
after some other Clang instance rebuilt the module file to bring it
up-to-date. The stale stat() results in the file manager would
trigger a second rebuild of the already-up-to-date module, causing
failures down the line.

The global module index now lazily resolves its module file references
to actual AST reader module files only after the module file has been
loaded, eliminating the stat-caching race. Moreover, the AST reader
can communicate to its caller that a module file is missing (rather
than simply being out-of-date), allowing us to simplify the
module-loading logic and allowing the compiler to recover if a
dependent module file ends up getting deleted.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177367 91177308-0d34-0410-b5e6-96231b3b80d8
Finish refactoring the tool selection logic.

The general pattern now is that Foobar::constructTool only creates tools
defined in the tools::foobar namespace and then delegates to the parent.

The remaining duplicated code is now in the tools themselves.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177368 91177308-0d34-0410-b5e6-96231b3b80d8
Minor optimization to r177367 to treat a module with missing dependencies as out-of-date rather than missing.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177369 91177308-0d34-0410-b5e6-96231b3b80d8
Remove stray semicolon

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177370 91177308-0d34-0410-b5e6-96231b3b80d8