Fixed by moving ProcessWarningOptions from Frontend into Basic. All of
the dependencies for ProcessWarningOptions were already in Basic, so
this was a small change.
llvm-svn: 207549
This patch checks whether the diagnostic options that could lead to
errors (principally -Werror) are consistent between when a module was
built and when it is loaded. If there are new -Werror flags, then the
module is rebuilt. In order to canonicalize the options we do this
check at the level of the constructed DiagnosticsEngine, which contains
the final set of diag to diagnostic level mappings. Currently we only
rebuild with the new diagnostic options, but we intend to refine this in
the future to include the union of the new and old flags, since we know
the old ones did not cause errors. System modules are only rebuilt when
-Wsystem-headers is enabled.
One oddity is that unlike checking language options, we don’t perform
this diagnostic option checking when loading from a precompiled header.
The reason for this is that the compiler cannot rebuild the PCH, so
anything that requires it to be rebuilt effectively leaks into the build
system. And in this case, that would mean the build system
understanding the complex relationship between diagnostic options and
the underlying diagnostic mappings, which is unreasonable. Skipping the
check is safe, because these options do not affect the generated AST.
You simply won’t get new build errors due to changed -Werror options
automatically, which is also true for non-module cases.
llvm-svn: 207477
To differentiate between two modules with the same name, we will
consider the path the module map file that they are defined by* part of
the ‘key’ for looking up the precompiled module (pcm file).
Specifically, this patch renames the precompiled module (pcm) files from
cache-path/<module hash>/Foo.pcm
to
cache-path/<module hash>/Foo-<hash of module map path>.pcm
In addition, I’ve taught the ASTReader to re-resolve the names of
imported modules during module loading so that if the header search
context changes between when a module was originally built and when it
is loaded we can rebuild it if necessary. For example, if module A
imports module B
first time:
clang -I /path/to/A -I /path/to/B ...
second time:
clang -I /path/to/A -I /different/path/to/B ...
will now rebuild A as expected.
* in the case of inferred modules, we use the module map file that
allowed the inference, not the __inferred_module.map file, since the
inferred file path is the same for every inferred module.
llvm-svn: 206201
Ben Langmuir