Commit Graph

7 Commits

Author SHA1 Message Date
Volodymyr Sapsai 8839e278ff [Modules] Improve error message when cannot find parent module for submodule definition.
Before the change the diagnostic for

    module unknown.submodule {}

was "error: expected module name" which is incorrect and misleading
because both "unknown" and "submodule" are valid module names.

We already have a better error message when a parent module is a
submodule itself and is missing. Make the error for a missing top-level
module more like the one for a submodule.

rdar://problem/64424407

Reviewed By: bruno

Differential Revision: https://reviews.llvm.org/D84458
2020-08-25 16:31:27 -07:00
Nico Weber 49532137d0 Make AST reading work better with LLVM_APPEND_VC_REV=NO
With LLVM_APPEND_VC_REV=NO, Modules/merge-lifetime-extended-temporary.cpp
would fail if it ran before a0f50d7316 (which changed
the serialization format) and then after, for these reasons:

1. With LLVM_APPEND_VC_REV=NO, the module hash before and after the
   change was the same.

2. Modules/merge-lifetime-extended-temporary.cpp is the only test
   we have that uses -fmodule-cache-path=%t that
   a) actually writes to the cache path
   b) doesn't do `rm -rf %t` at the top of the test

So the old run would write a module file, and then the new run would
try to load it, but the serialized format changed.

Do several things to fix this:

1. Include clang::serialization::VERSION_MAJOR/VERSION_MINOR in
   the module hash, so that when the AST format changes (...and
   we remember to bump these), we use a different module cache dir.
2. Bump VERSION_MAJOR, since a0f50d7316 changed the
   on-disk format in a way that a gch file written before that change
   can't be read after that change.
3. Add `rm -rf %t` to all tests that pass -fmodule-cache-path=%t.
   This is unnecessary from a correctness PoV after 1 and 2,
   but makes it so that we don't amass many cache dirs over time.
   (Arguably, it also makes it so that the test suite doesn't catch
   when we change the serialization format but don't bump
   clang::serialization::VERSION_MAJOR/VERSION_MINOR; oh well.)

Differential Revision: https://reviews.llvm.org/D73202
2020-01-27 22:08:37 -05:00
Richard Smith 040e12662a Support lazy stat'ing of files referenced by module maps.
This patch adds support for a `header` declaration in a module map to specify
certain `stat` information (currently, size and mtime) about that header file.
This has two purposes:

- It removes the need to eagerly `stat` every file referenced by a module map.
  Instead, we track a list of unresolved header files with each size / mtime
  (actually, for simplicity, we track submodules with such headers), and when
  attempting to look up a header file based on a `FileEntry`, we check if there
  are any unresolved header directives with that `FileEntry`'s size / mtime and
  perform deferred `stat`s if so.

- It permits a preprocessed module to be compiled without the original files
  being present on disk. The only reason we used to need those files was to get
  the `stat` information in order to do header -> module lookups when using the
  module. If we're provided with the `stat` information in the preprocessed
  module, we can avoid requiring the files to exist.

Unlike most `header` directives, if a `header` directive with `stat`
information has no corresponding on-disk file the enclosing module is *not*
marked unavailable (so that behavior is consistent regardless of whether we've
resolved a header directive, and so that preprocessed modules don't get marked
unavailable). We could actually do this for all `header` directives: the only
reason we mark the module unavailable if headers are missing is to give a
diagnostic slightly earlier (rather than waiting until we actually try to build
the module / load and validate its .pcm file).

Differential Revision: https://reviews.llvm.org/D33703

llvm-svn: 304515
2017-06-02 01:55:39 +00:00
Richard Smith ae6df27ef4 [modules] When diagnosing errors in module map files found by 'extern module' declarations, show how we got to that module map file.
llvm-svn: 242105
2015-07-14 02:06:01 +00:00
Richard Smith 8f4d3ff146 [modules] Restrict the module use-declaration to only appear in top-level
modules, and allow sub-modules of a module with a use-declaration to make use
of the nominated modules.

llvm-svn: 233323
2015-03-26 22:10:01 +00:00
Richard Smith 0414b8578e [modules] Accept //-style comments in module maps on purpose rather than by
accident, and accept them even when they begin '//*'.

llvm-svn: 229240
2015-02-14 05:32:00 +00:00
Richard Smith ac425e9165 PR22299: Relocate code for handling -fmodule-map-file= so that we don't try to
produce diagnostics with source locations before the diagnostics system is
ready for them.

llvm-svn: 226882
2015-01-23 00:01:13 +00:00