On Tue, 8 Feb 2022 at 21:18, Jonathan Wakely wrote: > > > On Tue, 8 Feb 2022 at 21:02, Dimitar Dimitrov <dimi...@dinux.eu> wrote: > >> On Mon, Feb 07, 2022 at 09:05:45PM +0000, Jonathan Wakely wrote: >> > On Mon, 7 Feb 2022 at 21:01, Jonathan Wakely <jwakely....@gmail.com> >> wrote: >> > >> > > >> > > >> > > On Mon, 7 Feb 2022 at 20:12, Dimitar Dimitrov <dimi...@dinux.eu> >> wrote: >> > > >> > >> On PRU target with newlib, we have the following combination in >> config.h: >> > >> /* #undef HAVE_DIRENT_H */ >> > >> #define HAVE_FCNTL_H 1 >> > >> #define HAVE_UNLINKAT 1 >> > >> >> > >> In newlib, targets which do not define dirent.h, get a build error >> when >> > >> including <dirent.h>: >> > >> >> > >> >> https://sourceware.org/git/?p=newlib-cygwin.git;a=blob;f=newlib/libc/include/sys/dirent.h;hb=HEAD >> > >> >> > >> While fs_dir.cc correctly checks for HAVE_FCNTL_H, dir-common.h >> doesn't, >> > >> and instead uses HAVE_DIRENT_H. This results in unlinkat() function >> call >> > >> in fs_dir.cc without the needed <fcntl.h> include in dir-common.h. >> Thus >> > >> a build failure: >> > >> .../gcc/libstdc++-v3/src/c++17/fs_dir.cc:151:11: error: >> ‘::unlinkat’ >> > >> has not been declared; did you mean ‘unlink’? >> > >> >> > >> Fix by encapsulating <fcntl.h> include with the correct check. >> > >> >> > > >> > > But there's no point doing anything in that file if we don't have >> > > <dirent.h>, the whole thing is unusable. There's no point making the >> > > members using unlinkat compile if you can't ever construct the type. >> > > >> > > So I think we want a different fix. >> > > >> > >> > >> > Maybe something like: >> > >> > --- a/libstdc++-v3/src/filesystem/dir-common.h >> > +++ b/libstdc++-v3/src/filesystem/dir-common.h >> > @@ -70,6 +70,8 @@ struct DIR { }; >> > inline DIR* opendir(const char*) { return nullptr; } >> > inline dirent* readdir(DIR*) { return nullptr; } >> > inline int closedir(DIR*) { return -1; } >> > +#undef _GLIBCXX_HAVE_DIRFD >> > +#undef _GLIBCXX_HAVE_UNLINKAT >> > #endif >> > } // namespace __gnu_posix >> Yes, this fixes the PRU target, and does not regress >> x86_64-pc-linux-gnu. >> > > Thanks for checking it. I'm just testing it myself on > powerpc64le-linux-gnu and will push when it finishes. > > Sorry for the delay, that's pushed to trunk now.
commit 3d5f4f76e6db0895181ebca538748379bfe6058f Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Feb 8 21:05:30 2022
libstdc++: Fix directory iterator build for newlib When building for newlib HAVE_OPENAT and HAVE_UNLINKAT are (sometimes?) defined, but <fcntl.h> is only included when HAVE_DIRENT_H is defined. Since directory iterators are completely useless without <dirent.h>, just override the HAVE_OPENAT and HAVE_UNLINKAT detection when we don't have <dirent.h>. libstdc++-v3/ChangeLog: * src/filesystem/dir-common.h (_GLIBCXX_HAVE_DIRFD): Undefine when <dirent.h> is not available. (_GLIBCXX_HAVE_UNLINKAT): Likewise. diff --git a/libstdc++-v3/src/filesystem/dir-common.h b/libstdc++-v3/src/filesystem/dir-common.h index 511b988f1c7..365fd527f4d 100644 --- a/libstdc++-v3/src/filesystem/dir-common.h +++ b/libstdc++-v3/src/filesystem/dir-common.h @@ -70,6 +70,8 @@ struct DIR { }; inline DIR* opendir(const char*) { return nullptr; } inline dirent* readdir(DIR*) { return nullptr; } inline int closedir(DIR*) { return -1; } +#undef _GLIBCXX_HAVE_DIRFD +#undef _GLIBCXX_HAVE_UNLINKAT #endif } // namespace __gnu_posix