When building relatively recent gcc ports (with C++ in them) against libc++ 17, you get errors similar to: In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/cp/module.cc:208: In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/system.h:239: In file included from /usr/include/c++/v1/vector:321: In file included from /usr/include/c++/v1/__format/formatter_bool.h:20: In file included from /usr/include/c++/v1/__format/formatter_integral.h:32: In file included from /usr/include/c++/v1/locale:202: /usr/include/c++/v1/__locale:546:5: error: '__abi_tag__' attribute only applies to structs, variables, functions, and namespaces 546 | _LIBCPP_INLINE_VISIBILITY | ^ /usr/include/c++/v1/__config:813:37: note: expanded from macro '_LIBCPP_INLINE_VISIBILITY' 813 | # define _LIBCPP_INLINE_VISIBILITY _LIBCPP_HIDE_FROM_ABI | ^ /usr/include/c++/v1/__config:792:26: note: expanded from macro '_LIBCPP_HIDE_FROM_ABI' 792 | __attribute__((__abi_tag__(_LIBCPP_TOSTRING(_LIBCPP_VERSIONED_IDENTIFIER)))) | ^ In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/cp/module.cc:208: In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/system.h:239: In file included from /usr/include/c++/v1/vector:321: In file included from /usr/include/c++/v1/__format/formatter_bool.h:20: In file included from /usr/include/c++/v1/__format/formatter_integral.h:32: In file included from /usr/include/c++/v1/locale:202: /usr/include/c++/v1/__locale:547:37: error: expected ';' at end of declaration list 547 | char_type toupper(char_type __c) const | ^ /usr/include/c++/v1/__locale:553:48: error: too many arguments provided to function-like macro invocation 553 | const char_type* toupper(char_type* __low, const char_type* __high) const | ^ /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/../include/safe-ctype.h:146:9: note: macro 'toupper' defined here 146 | #define toupper(c) do_not_use_toupper_with_safe_ctype | ^ This is because gcc/system.h includes safe-ctype.h which redefines ctype macros such as toupper, tolower, etc to "poison" them. However, it should only include the safe-ctype.h header *after* any C++ headers, such as <list>, <map>, <string>, etc, otherwise these might transitively include internal ctype headers (such as with libc++ 17), causing the above conflicts. Here is a patch that moves the safe-ctype.h inclusion to later in gcc/system.h, which solves this issue, and makes it possible to build against libc++ 17.
Created attachment 245139 [details] lang/gcc6-aux: fix build with libc++ 17
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A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/ports/commit/?id=fef10a5f06e752b07282123abe59196618649cac commit fef10a5f06e752b07282123abe59196618649cac Author: Dimitry Andric <dim@FreeBSD.org> AuthorDate: 2023-09-21 19:08:58 +0000 Commit: Dimitry Andric <dim@FreeBSD.org> CommitDate: 2023-09-23 16:24:07 +0000 lang/gcc6-aux: fix build with libc++ 17 When building relatively recent gcc ports (with C++ in them) against libc++ 17, you get errors similar to: In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/cp/module.cc:208: In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/system.h:239: In file included from /usr/include/c++/v1/vector:321: In file included from /usr/include/c++/v1/__format/formatter_bool.h:20: In file included from /usr/include/c++/v1/__format/formatter_integral.h:32: In file included from /usr/include/c++/v1/locale:202: /usr/include/c++/v1/__locale:546:5: error: '__abi_tag__' attribute only applies to structs, variables, functions, and namespaces 546 | _LIBCPP_INLINE_VISIBILITY | ^ /usr/include/c++/v1/__config:813:37: note: expanded from macro '_LIBCPP_INLINE_VISIBILITY' 813 | # define _LIBCPP_INLINE_VISIBILITY _LIBCPP_HIDE_FROM_ABI | ^ /usr/include/c++/v1/__config:792:26: note: expanded from macro '_LIBCPP_HIDE_FROM_ABI' 792 | __attribute__((__abi_tag__(_LIBCPP_TOSTRING(_LIBCPP_VERSIONED_IDENTIFIER)))) | ^ In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/cp/module.cc:208: In file included from /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/system.h:239: In file included from /usr/include/c++/v1/vector:321: In file included from /usr/include/c++/v1/__format/formatter_bool.h:20: In file included from /usr/include/c++/v1/__format/formatter_integral.h:32: In file included from /usr/include/c++/v1/locale:202: /usr/include/c++/v1/__locale:547:37: error: expected ';' at end of declaration list 547 | char_type toupper(char_type __c) const | ^ /usr/include/c++/v1/__locale:553:48: error: too many arguments provided to function-like macro invocation 553 | const char_type* toupper(char_type* __low, const char_type* __high) const | ^ /wrkdirs/usr/ports/lang/gcc12/work/gcc-12.2.0/gcc/../include/safe-ctype.h:146:9: note: macro 'toupper' defined here 146 | #define toupper(c) do_not_use_toupper_with_safe_ctype | ^ This is because gcc/system.h includes safe-ctype.h which redefines ctype macros such as toupper, tolower, etc to "poison" them. However, it should only include the safe-ctype.h header *after* any C++ headers, such as <list>, <map>, <string>, etc, otherwise these might transitively include internal ctype headers (such as with libc++ 17), causing the above conflicts. This commit moves the safe-ctype.h inclusion to later in gcc/system.h, which solves this issue, and makes it possible to build against libc++ 17. PR: 274036 Approved by: fluffy (maintainer) MFH: 2023Q3 lang/gcc6-aux/files/patch-gcc_system.h (new) | 42 ++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+)