On 11/12/18, Martin Sebor <mse...@gmail.com> wrote: > On 11/11/2018 04:33 PM, David Malcolm wrote: >> When gcc can't find a header file, it's a hard error that stops the >> build, >> typically requiring the user to mess around with compile flags, >> Makefiles, >> dependencies, and so forth. >> >> Often the exact search paths aren't obvious to the user. Consider the >> case where the include paths are injected via a tool such as pkg-config, >> such as e.g.: >> >> gcc $(pkg-config --cflags glib-2.0) demo.c >> >> This patch is an attempt at being more helpful for such cases. Given >> that >> the user can't proceed until the issue is resolved, I think it's >> reasonable >> to default to telling the user as much as possible about what happened. >> This patch list all of the search paths, and any close matches (e.g. for >> misspellings). >> >> Without the patch, the current behavior is: >> >> misspelled-header-1.c:1:10: fatal error: test-header.hpp: No such file or >> directory >> 1 | #include "test-header.hpp" >> | ^~~~~~~~~~~~~~~~~ >> compilation terminated. >> >> With the patch, the user gets this output: >> >> misspelled-header-1.c:1:10: fatal error: test-header.hpp: No such file or >> directory >> 1 | #include "test-header.hpp" >> | ^~~~~~~~~~~~~~~~~ >> misspelled-header-1.c:1:10: note: paths searched: >> misspelled-header-1.c:1:10: note: path: '' >> misspelled-header-1.c:1:10: note: not found: 'test-header.hpp' >> misspelled-header-1.c:1:10: note: close match: 'test-header.h' >> 1 | #include "test-header.hpp" >> | ^~~~~~~~~~~~~~~~~ >> | "test-header.h" >> misspelled-header-1.c:1:10: note: path: '/usr/include/glib-2.0' (via >> '-I') >> misspelled-header-1.c:1:10: note: not found: >> '/usr/include/glib-2.0/test-header.hpp' >> misspelled-header-1.c:1:10: note: path: '/usr/lib64/glib-2.0/include' >> (via '-I') >> misspelled-header-1.c:1:10: note: not found: >> '/usr/lib64/glib-2.0/include/test-header.hpp' >> misspelled-header-1.c:1:10: note: path: './include' (system directory) >> misspelled-header-1.c:1:10: note: not found: >> './include/test-header.hpp' >> misspelled-header-1.c:1:10: note: path: './include-fixed' (system >> directory) >> misspelled-header-1.c:1:10: note: not found: >> './include-fixed/test-header.hpp' >> misspelled-header-1.c:1:10: note: path: '/usr/local/include' (system >> directory) >> misspelled-header-1.c:1:10: note: not found: >> '/usr/local/include/test-header.hpp' >> misspelled-header-1.c:1:10: note: path: '/usr/include' (system >> directory) >> misspelled-header-1.c:1:10: note: not found: >> '/usr/include/test-header.hpp' >> compilation terminated. >> >> showing the paths that were tried, and why (e.g. the -I paths injected by >> the pkg-config invocation), and the .hpp vs .h issue (with a fix-it >> hint). >> >> It's verbose, but as I said above, the user can't proceed until they >> resolve it, so I think being verbose is appropriate here. >> >> Thoughts? > > I think printing the directories and especially the near matches > will be very helpful, especially for big projects with lots of -I > options. > > The output could be made substantially shorter, less repetitive, > and so easier to read -- basically cut in half -- by avoiding > most of the duplication and collapsing two notes into one, e.g. > like so: > > fatal error: test-header.hpp: No such file or directory > 1 | #include "test-header.hpp" > | ^~~~~~~~~~~~~~~~~ > note: paths searched: > note: -I '.' > note: close match: 'test-header.h' > 1 | #include "test-header.hpp" > | ^~~~~~~~~~~~~~~~~ > | "test-header.h" > note: -I '/usr/include/glib-2.0' > note: -I '/usr/lib64/glib-2.0/include' > note: -isystem './include' > note: -isystem './include-fixed' > note: -isystem '/usr/local/include' > note: -isystem '/usr/include' > > or by printing the directories in sections: > > note: -I paths searched: > note: '.' > note: close match: 'test-header.h' > 1 | #include "test-header.hpp" > | ^~~~~~~~~~~~~~~~~ > | "test-header.h" > note: '/usr/include/glib-2.0' > note: '/usr/lib64/glib-2.0/include' > note: -isystem paths searched: > note: './include' > note: './include-fixed' > note: '/usr/local/include' > note: '/usr/include' > > Martin > >
How would this interact with -Wmissing-include-dirs?