Currently there're two pages that both talk about "Modules" in clang, but
they're different. The one that describes C++ standard modules explicitly
spells out the difference but the other one which targeting Clang modules
doesn't.
This patch adds a link that refers to the C++ standard modules
one in Clang modules doc, as you usually got the later page when
googling. I believe this will make newcomers less confused.
Signed-off-by: Jun Zhang <jun@junz.org>
Differential Revision: https://reviews.llvm.org/D134105
The behavior is controlled by the `-fprebuilt-implicit-modules` option, and
allows searching for implicit modules in the prebuilt module cache paths.
The current command-line options for prebuilt modules do not allow to easily
maintain and use multiple versions of modules. Both the producer and users of
prebuilt modules are required to know the relationships between compilation
options and module file paths. Using a particular version of a prebuilt module
requires passing a particular option on the command line (e.g.
`-fmodule-file=[<name>=]<file>` or `-fprebuilt-module-path=<directory>`).
However the compiler already knows how to distinguish and automatically locate
implicit modules. Hence this proposal to introduce the
`-fprebuilt-implicit-modules` option. When set, it enables searching for
implicit modules in the prebuilt module paths (specified via
`-fprebuilt-module-path`). To not modify existing behavior, this search takes
place after the standard search for prebuilt modules. If not
Here is a workflow illustrating how both the producer and consumer of prebuilt
modules would need to know what versions of prebuilt modules are available and
where they are located.
clang -cc1 -x c modulemap -fmodules -emit-module -fmodule-name=foo -fmodules-cache-path=prebuilt_modules_v1 <config 1 options>
clang -cc1 -x c modulemap -fmodules -emit-module -fmodule-name=foo -fmodules-cache-path=prebuilt_modules_v2 <config 2 options>
clang -cc1 -x c modulemap -fmodules -emit-module -fmodule-name=foo -fmodules-cache-path=prebuilt_modules_v3 <config 3 options>
clang -cc1 -x c use.c -fmodules fmodule-map-file=modulemap -fprebuilt-module-path=prebuilt_modules_v1 <config 1 options>
clang -cc1 -x c use.c -fmodules fmodule-map-file=modulemap <non-prebuilt config options>
With prebuilt implicit modules, the producer can generate prebuilt modules as
usual, all in the same output directory. The same mechanisms as for implicit
modules take care of incorporating hashes in the path to distinguish between
module versions.
Note that we do not specify the output module filename, so `-o` implicit modules are generated in the cache path `prebuilt_modules`.
clang -cc1 -x c modulemap -fmodules -emit-module -fmodule-name=foo -fmodules-cache-path=prebuilt_modules <config 1 options>
clang -cc1 -x c modulemap -fmodules -emit-module -fmodule-name=foo -fmodules-cache-path=prebuilt_modules <config 2 options>
clang -cc1 -x c modulemap -fmodules -emit-module -fmodule-name=foo -fmodules-cache-path=prebuilt_modules <config 3 options>
The user can now simply enable prebuilt implicit modules and point to the
prebuilt modules cache. No need to "parse" command-line options to decide
what prebuilt modules (paths) to use.
clang -cc1 -x c use.c -fmodules fmodule-map-file=modulemap -fprebuilt-module-path=prebuilt_modules -fprebuilt-implicit-modules <config 1 options>
clang -cc1 -x c use.c -fmodules fmodule-map-file=modulemap -fprebuilt-module-path=prebuilt_modules -fprebuilt-implicit-modules <non-prebuilt config options>
This is for example particularly useful in a use-case where compilation is
expensive, and the configurations expected to be used are predictable, but not
controlled by the producer of prebuilt modules. Modules for the set of
predictable configurations can be prebuilt, and using them does not require
"parsing" the configuration (command-line options).
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D68997
Summary:
This updates all places in documentation that refer to "Mac OS X", "OS X", etc.
to instead use the modern name "macOS" when no specific version number is
mentioned.
If a specific version is mentioned, this attempts to use the OS name at the time
of that version:
* Mac OS X for 10.0 - 10.7
* OS X for 10.8 - 10.11
* macOS for 10.12 - present
Reviewers: JDevlieghere
Subscribers: mgorny, christof, arphaman, cfe-commits, lldb-commits, libcxx-commits, llvm-commits
Tags: #clang, #lldb, #libc, #llvm
Differential Revision: https://reviews.llvm.org/D62654
llvm-svn: 362113
Allows module map writers to add build requirements based on
platform/os. This helps when target features and language dialects
aren't enough to conditionalize building a module, among other things,
it allow module maps for different platforms to live in the same file.
rdar://problem/43909745
Differential Revision: https://reviews.llvm.org/D51910
llvm-svn: 342499
We used to advertise private modules to be declared as submodules
(Foo.Private). This has proven to not scale well since private headers
might carry several dependencies, introducing unwanted content into the
main module and often causing dep cycles.
Change the canonical way to name it to Foo_Private, forcing private
modules as top level ones, and provide warnings under -Wprivate-module
to suggest fixes for other private naming. Update documentation to
reflect that.
rdar://problem/31173501
llvm-svn: 321337
Introduce a new "export_as" directive for top-level modules, which
indicates that the current module is a "private" module whose symbols
will eventually be exported through the named "public" module. This is
in support of a common pattern in the Darwin ecosystem where a single
public framework is constructed of several private frameworks, with
(currently) header duplication and some support from the linker.
Addresses rdar://problem/34438420.
llvm-svn: 313316
Extend the -fmodule-file option to support the [<name>=]<file> value format.
If the name is omitted, then the old semantics is preserved (the module file
is loaded whether needed or not). If the name is specified, then the mapping
is treated as just another prebuilt module search mechanism, similar to
-fprebuilt-module-path, and the module file is only loaded if actually used
(e.g., via import). With one exception: this mapping also overrides module
file references embedded in other modules (which can be useful if module files
are moved/renamed as often happens during remote compilation).
This override semantics requires some extra work: we now store the module name
in addition to the file name in the serialized AST representation.
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D35020
llvm-svn: 312220
Extend the -fmodule-file option to support the [<name>=]<file> value format.
If the name is omitted, then the old semantics is preserved (the module file
is loaded whether needed or not). If the name is specified, then the mapping
is treated as just another prebuilt module search mechanism, similar to
-fprebuilt-module-path, and the module file is only loaded if actually used
(e.g., via import). With one exception: this mapping also overrides module
file references embedded in other modules (which can be useful if module files
are moved/renamed as often happens during remote compilation).
This override semantics requires some extra work: we now store the module name
in addition to the file name in the serialized AST representation.
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D35020
llvm-svn: 312105
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
Summary: In order for libc++ to add `<experimental/coroutine>` to its module map, there has to be a feature that can be used to detect if coroutines support is enabled in Clang.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D33538
llvm-svn: 304107
Summary: In order for libc++ to add `<experimental/coroutine>` to its module map, there has to be a feature that can be used to detect if coroutines support is enabled in Clang.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D33538
llvm-svn: 304054
The 'no_undeclared_includes' attribute should be used in a module to
tell that only non-modular headers and headers from used modules are
accepted.
The main motivation behind this is to prevent dep cycles between system
libraries (such as darwin) and libc++.
Patch by Richard Smith!
llvm-svn: 284797
This adds support for modules that require (non-)freestanding
environment, such as the compiler builtin mm_malloc submodule.
Differential Revision: https://reviews.llvm.org/D23871
llvm-svn: 280613
This adds support for modules that require (no-)gnu-inline-asm
environment, such as the compiler builtin cpuid submodule.
This is the gnu-inline-asm variant of https://reviews.llvm.org/D23871
Differential Revision: https://reviews.llvm.org/D23905
rdar://problem/26931199
llvm-svn: 280159
In this mode, there is no need to load any module map and the programmer can
simply use "@import" syntax to load the module directly from a prebuilt
module path. When loading from prebuilt module path, we don't support
rebuilding of the module files and we ignore compatible configuration
mismatches.
rdar://27290316
Differential Revision: http://reviews.llvm.org/D23125
llvm-svn: 279096
If this flag is set, we error out when a module build is required. This is
useful in environments where all required modules are passed via -fmodule-file.
llvm-svn: 230006
This allows a module to specify that it logically contains a file, but that
said file is non-modular and intended for textual inclusion. This allows
layering checks to work properly in the presence of such files.
llvm-svn: 220448
#include_next interacts poorly with modules: it depends on where in the list of
include paths the current file was found. Files covered by module maps are not
found in include search paths when building the module (and are not found in
include search paths when @importing the module either), so this isn't really
meaningful. Instead, we fake up the result that #include_next *should* have
given: find the first path that would have resulted in the given file being
picked, and search from there onwards.
llvm-svn: 220177
being on by default. -fno-cxx-modules can still be used to enable C modules but
not C++ modules, but C++ modules is not significantly less stable than C
modules any more.
Also remove some of the scare words from the modules documentation. We're
certainly not going to remove modules support (though we might change the
interface), and it works well enough to bootstrap and build lots of
non-trivial code.
Note that this does not represent a commitment to the current interface nor
implementation, and we still intend to follow whatever direction the C and C++
committees take regarding modules support.
llvm-svn: 218717
Jun Zhang