commit: ff1ba90cc398eb99d4e5514e0f0332c2105c5872 Author: Sam James <sam <AT> gentoo <DOT> org> AuthorDate: Tue Mar 25 02:32:13 2025 +0000 Commit: Sam James <sam <AT> gentoo <DOT> org> CommitDate: Tue Mar 25 02:32:13 2025 +0000 URL: https://gitweb.gentoo.org/proj/gcc-patches.git/commit/?id=ff1ba90c
Revert "15.0.0: drop musttail workaround" This reverts commit ebea0f72bf6bcc9c53105a689beb6263047b35c8. More issues. Signed-off-by: Sam James <sam <AT> gentoo.org> .../77_all_PR119376-Disable-clang-musttail.patch | 200 +++++++++++++++++++++ 15.0.0/gentoo/README.history | 1 + 2 files changed, 201 insertions(+) diff --git a/15.0.0/gentoo/77_all_PR119376-Disable-clang-musttail.patch b/15.0.0/gentoo/77_all_PR119376-Disable-clang-musttail.patch new file mode 100644 index 0000000..3af4ab4 --- /dev/null +++ b/15.0.0/gentoo/77_all_PR119376-Disable-clang-musttail.patch @@ -0,0 +1,200 @@ +https://inbox.sourceware.org/gcc-patches/20250320013102.1336516-1-a...@firstfloor.org/ + +From 592f60bef27cb60ea6405ca8603449fc4d92e640 Mon Sep 17 00:00:00 2001 +Message-ID: <592f60bef27cb60ea6405ca8603449fc4d92e640.1742435883.git....@gentoo.org> +From: Andi Kleen <a...@gcc.gnu.org> +Date: Wed, 19 Mar 2025 18:31:02 -0700 +Subject: [PATCH] PR119376: Disable clang musttail + +There are multiple reports (see PR 119376) now where semantic differences +in the gcc musttail implementation break existing programs written for the clang +variant. + +Even though that can be all hopefully fixed eventually, +for the gcc 15 release it seems safer to disable clang::musttail, +and only keep gnu::musttail. + +That means that programs that use __has_c_attribute to check for +clang::musttail must opt-in explicitly. + +Reported-by: Sam James + +gcc/c/ChangeLog: + + PR ipa/119376 + * c-parser.cc (c_parser_handle_musttail): Drop clang namespace + check. + +gcc/cp/ChangeLog: + + PR ipa/119376 + * parser.cc (cp_parser_jump_statement): Drop clang namespace + check. + +gcc/ChangeLog: + + PR ipa/119376 + * doc/extend.texi: Drop clang::musttail reference. + +gcc/testsuite/ChangeLog: + +PR ipa/119376 + * c-c++-common/musttail23.c: Don't use clang::musttail + * c-c++-common/musttail24.c: Dito. + * c-c++-common/musttail3.c: Dito. + * g++.dg/musttail14.C: Dito. +--- + gcc/c/c-parser.cc | 5 ----- + gcc/cp/parser.cc | 6 ------ + gcc/doc/extend.texi | 2 +- + gcc/testsuite/c-c++-common/musttail23.c | 10 +++++----- + gcc/testsuite/c-c++-common/musttail24.c | 6 ------ + gcc/testsuite/c-c++-common/musttail3.c | 6 +++--- + gcc/testsuite/g++.dg/musttail14.C | 4 ++-- + 7 files changed, 11 insertions(+), 28 deletions(-) + +diff --git a/gcc/c/c-parser.cc b/gcc/c/c-parser.cc +index d49d5c58659f..79654448acaa 100644 +--- a/gcc/c/c-parser.cc ++++ b/gcc/c/c-parser.cc +@@ -7409,11 +7409,6 @@ c_parser_handle_musttail (c_parser *parser, tree std_attrs, attr_state &attr) + std_attrs = remove_attribute ("gnu", "musttail", std_attrs); + attr.musttail_p = true; + } +- if (lookup_attribute ("clang", "musttail", std_attrs)) +- { +- std_attrs = remove_attribute ("clang", "musttail", std_attrs); +- attr.musttail_p = true; +- } + } + return std_attrs; + } +diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc +index 2fb1dc5992d4..da7700b55c64 100644 +--- a/gcc/cp/parser.cc ++++ b/gcc/cp/parser.cc +@@ -15342,12 +15342,6 @@ cp_parser_jump_statement (cp_parser* parser, tree &std_attrs) + musttail_p = true; + std_attrs = remove_attribute ("gnu", "musttail", std_attrs); + } +- /* Support this for compatibility. */ +- if (lookup_attribute ("clang", "musttail", std_attrs)) +- { +- musttail_p = true; +- std_attrs = remove_attribute ("clang", "musttail", std_attrs); +- } + + tree ret_expr = expr; + if (ret_expr && TREE_CODE (ret_expr) == TARGET_EXPR) +diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi +index b919df914648..50f95e968ff9 100644 +--- a/gcc/doc/extend.texi ++++ b/gcc/doc/extend.texi +@@ -10241,7 +10241,7 @@ have to optimize it to just @code{return 42 + 42;}. + @cindex @code{musttail} statement attribute + @item musttail + +-The @code{gnu::musttail} or @code{clang::musttail} standard attribute ++The @code{gnu::musttail} standard attribute + or @code{musttail} GNU attribute can be applied to a @code{return} statement + with a return-value expression that is a function call. It asserts that the + call must be a tail call that does not allocate extra stack space, so it is +diff --git a/gcc/testsuite/c-c++-common/musttail23.c b/gcc/testsuite/c-c++-common/musttail23.c +index d2ba70b03250..1ceab1165129 100644 +--- a/gcc/testsuite/c-c++-common/musttail23.c ++++ b/gcc/testsuite/c-c++-common/musttail23.c +@@ -19,10 +19,10 @@ foo (int x) + [[gnu::musttail (1, "", 3)]] return bar (); /* { dg-error "'musttail' attribute does not take any arguments" } */ + /* { dg-error "expected" "" { target c } .-1 } */ + if (x == 3) +- [[clang::musttail (1)]] return bar (); /* { dg-error "'musttail' attribute does not take any arguments" } */ ++ [[gnu::musttail (1)]] return bar (); /* { dg-error "'musttail' attribute does not take any arguments" } */ + /* { dg-error "expected" "" { target c } .-1 } */ + if (x == 4) +- [[clang::musttail (1, "", 3)]] return bar (); /* { dg-error "'musttail' attribute does not take any arguments" } */ ++ [[gnu::musttail (1, "", 3)]] return bar (); /* { dg-error "'musttail' attribute does not take any arguments" } */ + /* { dg-error "expected" "" { target c } .-1 } */ + if (x == 5) + __attribute__((fallthrough, musttail)) return bar (); /* { dg-warning "attribute 'musttail' mixed with other attributes on 'return' statement" "" { target c } } */ +@@ -32,14 +32,14 @@ foo (int x) + [[fallthrough]] [[gnu::musttail]] return bar (); /* { dg-warning "'fallthrough' attribute ignored" "" { target c } } */ + /* { dg-warning "attributes at the beginning of statement are ignored" "" { target c++ } .-1 } */ + if (x == 7) +- [[clang::musttail, fallthrough]] return bar (); /* { dg-warning "'fallthrough' attribute ignored" "" { target c } } */ ++ [[gnu::musttail, fallthrough]] return bar (); /* { dg-warning "'fallthrough' attribute ignored" "" { target c } } */ + /* { dg-warning "attributes at the beginning of statement are ignored" "" { target c++ } .-1 } */ + if (x == 8) + __attribute__((musttail, musttail)) return bar (); + if (x == 9) + [[gnu::musttail, gnu::musttail]] return bar (); + if (x == 10) +- [[clang::musttail]] [[clang::musttail]] return bar (); ++ [[gnu::musttail]] [[gnu::musttail]] return bar (); + if (x == 11) +- [[clang::musttail]] [[gnu::musttail]] return bar (); ++ [[gnu::musttail]] [[gnu::musttail]] return bar (); + } +diff --git a/gcc/testsuite/c-c++-common/musttail24.c b/gcc/testsuite/c-c++-common/musttail24.c +index 10c2d3f188d8..26b8dbfb4c8e 100644 +--- a/gcc/testsuite/c-c++-common/musttail24.c ++++ b/gcc/testsuite/c-c++-common/musttail24.c +@@ -8,14 +8,8 @@ + #if !__has_cpp_attribute (gnu::musttail) + #error missing gnu::musttail attribute + #endif +-#if !__has_cpp_attribute (clang::musttail) +-#error missing clang::musttail attribute +-#endif + #else + #if !__has_c_attribute (gnu::musttail) + #error missing gnu::musttail attribute + #endif +-#if !__has_c_attribute (clang::musttail) +-#error missing clang::musttail attribute +-#endif + #endif +diff --git a/gcc/testsuite/c-c++-common/musttail3.c b/gcc/testsuite/c-c++-common/musttail3.c +index 7499fd6460b4..daedca28852a 100644 +--- a/gcc/testsuite/c-c++-common/musttail3.c ++++ b/gcc/testsuite/c-c++-common/musttail3.c +@@ -11,7 +11,7 @@ struct str + cstruct (int x) + { + if (x < 10) +- [[clang::musttail]] return cstruct (x + 1); ++ [[gnu::musttail]] return cstruct (x + 1); + return ((struct str){ x, 0 }); + } + +@@ -19,11 +19,11 @@ int + foo (int x) + { + if (x < 10) +- [[clang::musttail]] return foo2 (x, 29); ++ [[gnu::musttail]] return foo2 (x, 29); + if (x < 100) + { + int k = foo (x + 1); +- [[clang::musttail]] return k; /* { dg-error "cannot tail-call: " } */ ++ [[gnu::musttail]] return k; /* { dg-error "cannot tail-call: " } */ + } + return x; + } +diff --git a/gcc/testsuite/g++.dg/musttail14.C b/gcc/testsuite/g++.dg/musttail14.C +index 810b45546d61..e4764a3bc03b 100644 +--- a/gcc/testsuite/g++.dg/musttail14.C ++++ b/gcc/testsuite/g++.dg/musttail14.C +@@ -58,8 +58,8 @@ garply (int x) + case 3: + __attribute__(()) [[gnu::musttail]] __attribute__(()) [[]] __attribute__(()) return qux (45); + case 4: +- [[]] __attribute__(()) [[clang::musttail]] __attribute__(()) [[]] return corge (46); ++ [[]] __attribute__(()) [[gnu::musttail]] __attribute__(()) [[]] return corge (46); + default: +- __attribute__(()) [[clang::musttail]] __attribute__(()) [[]] __attribute__(()) return freddy (47); ++ __attribute__(()) [[gnu::musttail]] __attribute__(()) [[]] __attribute__(()) return freddy (47); + } + } +-- +2.49.0 + diff --git a/15.0.0/gentoo/README.history b/15.0.0/gentoo/README.history index 92b88c3..2a32843 100644 --- a/15.0.0/gentoo/README.history +++ b/15.0.0/gentoo/README.history @@ -1,5 +1,6 @@ 49 ???? + + 77_all_PR119376-Disable-clang-musttail.patch + 80_all_PR119428.patch 48 24 March 2025
