Hi, This patch adds initial support for ISO C++'s [P1689R5][], a format for describing C++ module requirements and provisions based on the source code. This is required because compiling C++ with modules is not embarrassingly parallel and need to be ordered to ensure that `import some_module;` can be satisfied in time by making sure that the TU with `export import some_module;` is compiled first.
[P1689R5]: https://isocpp.org/files/papers/P1689R5.html I'd like feedback on the approach taken here with respect to the user-visible flags. I'll also note that header units are not supported at this time because the current `-E` behavior with respect to `import <some_header>;` is to search for an appropriate `.gcm` file which is not something such a "scan" can support. A new mode will likely need to be created (e.g., replacing `-E` with `-fc++-module-scanning` or something) where headers are looked up "normally" and processed only as much as scanning requires. For the record, Clang has patches with similar flags and behavior by Chuanqi Xu here: https://reviews.llvm.org/D134269 with the same flags. Thanks, --Ben --- v1 -> v2: - removal of the `deps_write(extra)` parameter to option-checking where ndeeded - default parameter of `cpp_finish(fdeps_stream = NULL)` - unification of libcpp UTF-8 validity functions from v1 - test cases for flag parsing states (depflags-*) and p1689 output (p1689-*) Ben Boeckel (3): libcpp: reject codepoints above 0x10FFFF libcpp: add a function to determine UTF-8 validity of a C string p1689r5: initial support gcc/ChangeLog | 5 + gcc/c-family/ChangeLog | 6 + gcc/c-family/c-opts.cc | 40 +++- gcc/c-family/c.opt | 12 + gcc/cp/ChangeLog | 5 + gcc/cp/module.cc | 3 +- gcc/doc/invoke.texi | 15 ++ gcc/testsuite/ChangeLog | 7 + gcc/testsuite/g++.dg/modules/depflags-f-MD.C | 2 + gcc/testsuite/g++.dg/modules/depflags-f.C | 1 + gcc/testsuite/g++.dg/modules/depflags-fi.C | 3 + gcc/testsuite/g++.dg/modules/depflags-fj-MD.C | 3 + gcc/testsuite/g++.dg/modules/depflags-fj.C | 4 + .../g++.dg/modules/depflags-fjo-MD.C | 4 + gcc/testsuite/g++.dg/modules/depflags-fjo.C | 5 + gcc/testsuite/g++.dg/modules/depflags-fo-MD.C | 3 + gcc/testsuite/g++.dg/modules/depflags-fo.C | 4 + gcc/testsuite/g++.dg/modules/depflags-j-MD.C | 2 + gcc/testsuite/g++.dg/modules/depflags-j.C | 3 + gcc/testsuite/g++.dg/modules/depflags-jo-MD.C | 3 + gcc/testsuite/g++.dg/modules/depflags-jo.C | 4 + gcc/testsuite/g++.dg/modules/depflags-o-MD.C | 2 + gcc/testsuite/g++.dg/modules/depflags-o.C | 3 + gcc/testsuite/g++.dg/modules/modules.exp | 11 + gcc/testsuite/g++.dg/modules/p1689-1.C | 18 ++ gcc/testsuite/g++.dg/modules/p1689-1.exp.json | 27 +++ gcc/testsuite/g++.dg/modules/p1689-2.C | 16 ++ gcc/testsuite/g++.dg/modules/p1689-2.exp.json | 16 ++ gcc/testsuite/g++.dg/modules/p1689-3.C | 14 ++ gcc/testsuite/g++.dg/modules/p1689-3.exp.json | 16 ++ gcc/testsuite/g++.dg/modules/p1689-4.C | 14 ++ gcc/testsuite/g++.dg/modules/p1689-4.exp.json | 14 ++ gcc/testsuite/g++.dg/modules/p1689-5.C | 14 ++ gcc/testsuite/g++.dg/modules/p1689-5.exp.json | 14 ++ gcc/testsuite/g++.dg/modules/test-p1689.py | 222 ++++++++++++++++++ gcc/testsuite/lib/modules.exp | 71 ++++++ libcpp/ChangeLog | 23 ++ libcpp/charset.cc | 22 +- libcpp/include/cpplib.h | 12 +- libcpp/include/mkdeps.h | 17 +- libcpp/init.cc | 13 +- libcpp/internal.h | 2 + libcpp/mkdeps.cc | 149 +++++++++++- 43 files changed, 823 insertions(+), 21 deletions(-) create mode 100644 gcc/testsuite/g++.dg/modules/depflags-f-MD.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-f.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-fi.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-fj-MD.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-fj.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-fjo-MD.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-fjo.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-fo-MD.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-fo.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-j-MD.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-j.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-jo-MD.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-jo.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-o-MD.C create mode 100644 gcc/testsuite/g++.dg/modules/depflags-o.C create mode 100644 gcc/testsuite/g++.dg/modules/p1689-1.C create mode 100644 gcc/testsuite/g++.dg/modules/p1689-1.exp.json create mode 100644 gcc/testsuite/g++.dg/modules/p1689-2.C create mode 100644 gcc/testsuite/g++.dg/modules/p1689-2.exp.json create mode 100644 gcc/testsuite/g++.dg/modules/p1689-3.C create mode 100644 gcc/testsuite/g++.dg/modules/p1689-3.exp.json create mode 100644 gcc/testsuite/g++.dg/modules/p1689-4.C create mode 100644 gcc/testsuite/g++.dg/modules/p1689-4.exp.json create mode 100644 gcc/testsuite/g++.dg/modules/p1689-5.C create mode 100644 gcc/testsuite/g++.dg/modules/p1689-5.exp.json create mode 100644 gcc/testsuite/g++.dg/modules/test-p1689.py create mode 100644 gcc/testsuite/lib/modules.exp base-commit: f95d3d5de72a1c43e8d529bad3ef59afc3214705 -- 2.37.3
