Hi! My recent change to enable _Float{16,32,64,128,32x,64x,128x} for C++ apparently broke bootstrap on some Debian/Ubuntu setups. Those multiarch targets put some headers into /usr/include/x86_64-linux-gnu/bits/ etc. subdirectory instead of /usr/include/bits/. This is handled by /* /usr/include comes dead last. */ { NATIVE_SYSTEM_HEADER_DIR, NATIVE_SYSTEM_HEADER_COMPONENT, 0, 0, 1, 2 }, { NATIVE_SYSTEM_HEADER_DIR, NATIVE_SYSTEM_HEADER_COMPONENT, 0, 0, 1, 0 }, in cppdefault.cc, where the 2 in the last element of the first initializer means the entry is ignored on non-multiarch and suffixed by the multiarch dir otherwise, so installed gcc has search path like: /home/jakub/gcc/obj01inst/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/13.0.0/include /home/jakub/gcc/obj01inst/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/13.0.0/include-fixed /usr/local/include /usr/include/x86_64-linux-gnu /usr/include (when installed with DESTDIR=/home/jakub/gcc/obj01inst). Now, when fixincludes is run, it is processing the whole /usr/include dir and all its subdirectories, so floatn{,-common.h} actually go into .../include-fixed/x86_64-linux-gnu/bits/floatn{,-common.h} because that is where they appear in /usr/include too. In some setups, /usr/include also contains /usr/include/bits -> x86_64-linux-gnu/bits symlink and after the r13-2896 tweak it works. In other setups there is no /usr/include/bits symlink and when one #include <bits/floatn.h> given the above search path, it doesn't find the fixincluded header, as /home/jakub/gcc/obj01inst/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/13.0.0/include-fixed/bits/floatn.h doesn't exist and /home/jakub/gcc/obj01inst/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/13.0.0/include-fixed/x86_64-linux-gnu/bits/floatn.h isn't searched and so /usr/include/x86_64-linux-gnu/bits/floatn.h wins and we fail because of typedef whatever _Float128; and similar. The following patch ought to fix this. The first hunk by arranging that the installed search path actually looks like: /home/jakub/gcc/obj01inst/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/13.0.0/include /home/jakub/gcc/obj01inst/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/13.0.0/include-fixed/x86_64-linux-gnu /home/jakub/gcc/obj01inst/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/13.0.0/include-fixed /usr/local/include /usr/include/x86_64-linux-gnu /usr/include and thus for include-fixed it treats it the same as /usr/include. The second FIXED_INCLUDE_DIR entry there is: { FIXED_INCLUDE_DIR, "GCC", 0, 0, 0, /* A multilib suffix needs adding if different multilibs use different headers. */ #ifdef SYSROOT_HEADERS_SUFFIX_SPEC 1 #else 0 #endif }, where SYSROOT_HEADERS_SUFFIX_SPEC is defined only on vxworks or mips*-mti-linux and arranges for multilib path to be appended there. Neither of those systems is multiarch. This isn't enough, because when using the -B option, the driver adds -isystem .../include-fixed in another place, so the second hunk modifies that spot the same. /home/jakub/gcc/obj01/gcc/xgcc -B /home/jakub/gcc/obj01/gcc/ then has search path: /home/jakub/gcc/obj01/gcc/include /home/jakub/gcc/obj01/gcc/include-fixed/x86_64-linux-gnu /home/jakub/gcc/obj01/gcc/include-fixed /usr/local/include /usr/include/x86_64-linux-gnu /usr/include which again is what I think we want to achieve.
Bootstrapped/regtested on x86_64-linux (Debian on GCCFarm, though with the /usr/include/bits -> x86_64-linux-gnu/bits symlink). Ok for trunk? 2022-09-29 Jakub Jelinek <ja...@redhat.com> PR bootstrap/107059 * cppdefault.cc (cpp_include_defaults): If SYSROOT_HEADERS_SUFFIX_SPEC isn't defined, add FIXED_INCLUDE_DIR entry with multilib flag 2 before FIXED_INCLUDE_DIR entry with multilib flag 0. * gcc.cc (do_spec_1): If multiarch_dir, add include-fixed/multiarch_dir paths before include-fixed paths. --- gcc/cppdefault.cc.jj 2022-01-18 11:58:59.411984500 +0100 +++ gcc/cppdefault.cc 2022-09-28 12:11:47.923603783 +0200 @@ -74,6 +74,9 @@ const struct default_include cpp_include #endif #ifdef FIXED_INCLUDE_DIR /* This is the dir for fixincludes. */ +#ifndef SYSROOT_HEADERS_SUFFIX_SPEC + { FIXED_INCLUDE_DIR, "GCC", 0, 0, 0, 2 }, +#endif { FIXED_INCLUDE_DIR, "GCC", 0, 0, 0, /* A multilib suffix needs adding if different multilibs use different headers. */ --- gcc/gcc.cc 2022-09-23 09:02:56.809314447 +0200 +++ gcc/gcc.cc 2022-09-28 21:02:29.751933657 +0200 @@ -6400,6 +6400,18 @@ do_spec_1 (const char *spec, int inswitc if (*sysroot_hdrs_suffix_spec) info.append = concat (info.append, dir_separator_str, multilib_dir, NULL); + else if (multiarch_dir) + { + /* For multiarch, search include-fixed/<multiarch-dir> + before include-fixed. */ + info.append = concat (info.append, dir_separator_str, + multiarch_dir, NULL); + info.append_len = strlen (info.append); + for_each_path (&include_prefixes, false, info.append_len, + spec_path, &info); + + info.append = "include-fixed"; + } info.append_len = strlen (info.append); for_each_path (&include_prefixes, false, info.append_len, spec_path, &info); Jakub