{"id":2220970,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2220970/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/patch/20260408135939.266955-1-tkaminsk@redhat.com/","project":{"id":17,"url":"http://patchwork.ozlabs.org/api/1.1/projects/17/?format=json","name":"GNU Compiler Collection","link_name":"gcc","list_id":"gcc-patches.gcc.gnu.org","list_email":"gcc-patches@gcc.gnu.org","web_url":null,"scm_url":null,"webscm_url":null},"msgid":"<20260408135939.266955-1-tkaminsk@redhat.com>","date":"2026-04-08T13:59:08","name":"libstdc++: Defined __cpp_lib_replaceable_contract_violation_handler.","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"dc7b53d506df2ffabbd2bd79781ecaa9205ca6de","submitter":{"id":90409,"url":"http://patchwork.ozlabs.org/api/1.1/people/90409/?format=json","name":"Tomasz Kamiński","email":"tkaminsk@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/gcc/patch/20260408135939.266955-1-tkaminsk@redhat.com/mbox/","series":[{"id":499145,"url":"http://patchwork.ozlabs.org/api/1.1/series/499145/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/list/?series=499145","date":"2026-04-08T13:59:08","name":"libstdc++: Defined __cpp_lib_replaceable_contract_violation_handler.","version":1,"mbox":"http://patchwork.ozlabs.org/series/499145/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2220970/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2220970/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","gcc-patches@gcc.gnu.org"],"Delivered-To":["patchwork-incoming@legolas.ozlabs.org","gcc-patches@gcc.gnu.org"],"Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=g/ePBHdJ;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org\n (client-ip=38.145.34.32; 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charset=\"US-ASCII\"; x-default=true","X-BeenThere":"gcc-patches@gcc.gnu.org","X-Mailman-Version":"2.1.30","Precedence":"list","List-Id":"Gcc-patches mailing list ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org"},"content":"This implements P3886R0: Wording for AT1-057, by defining the\n__cpp_lib_replaceable_contract_violation_handler. The macro is defined\nonly if contracts are supported (i.e. under same conditions as\n__cpp_lib_contracts).\n\nGCC supports providing custom violation handler by providing an separate\ndefintion of handle_contract_violation. This is supported on the targets\nthat uses ELF format, so the macro is defined for with non-zero value\nfor them.\n\nlibstdc++-v3/ChangeLog:\n\n\t* include/bits/version.def (replaceable_contract_violation_handler)\n\t[(__cplusplus > 202302L) && (__cpp_contracts >= 202502L)]:\n\tDefine to 202603 for ELF targets, and 0 otherwise.\n\t* include/bits/version.h: Regenerate.\n\t* include/std/contracts: Define\n\t__cpp_lib_replaceable_contract_violation_handler.\n---\nFrom the discussion with Jason, this for sure is supported for ELF\ntargets. We were not sure regarding Darwin, but we could always expand\nthe set of targets where macro is defined.\n\nOK for trunk?\n\n libstdc++-v3/include/bits/version.def | 15 +++++++++++++++\n libstdc++-v3/include/bits/version.h | 15 +++++++++++++++\n libstdc++-v3/include/std/contracts | 1 +\n 3 files changed, 31 insertions(+)","diff":"diff --git a/libstdc++-v3/include/bits/version.def b/libstdc++-v3/include/bits/version.def\nindex cfb90533ce4..65a1d6d2660 100644\n--- a/libstdc++-v3/include/bits/version.def\n+++ b/libstdc++-v3/include/bits/version.def\n@@ -2351,6 +2351,21 @@ ftms = {\n };\n };\n \n+ftms = {\n+ name = replaceable_contract_violation_handler;\n+ values = {\n+ v = 202603;\n+ cxxmin = 26;\n+ extra_cond = \"__cpp_contracts >= 202502L \"\n+ \"&& __ELF__\";\n+ };\n+ values = {\n+ v = 0;\n+ cxxmin = 26;\n+ extra_cond = \"__cpp_contracts >= 202502L\";\n+ };\n+};\n+\n ftms = {\n name = simd;\n values = {\ndiff --git a/libstdc++-v3/include/bits/version.h b/libstdc++-v3/include/bits/version.h\nindex 22dd31b9d32..4059a8a767b 100644\n--- a/libstdc++-v3/include/bits/version.h\n+++ b/libstdc++-v3/include/bits/version.h\n@@ -2626,6 +2626,21 @@\n #endif /* !defined(__cpp_lib_contracts) */\n #undef __glibcxx_want_contracts\n \n+#if !defined(__cpp_lib_replaceable_contract_violation_handler)\n+# if (__cplusplus > 202302L) && (__cpp_contracts >= 202502L && __ELF__)\n+# define __glibcxx_replaceable_contract_violation_handler 202603L\n+# if defined(__glibcxx_want_all) || defined(__glibcxx_want_replaceable_contract_violation_handler)\n+# define __cpp_lib_replaceable_contract_violation_handler 202603L\n+# endif\n+# elif (__cplusplus > 202302L) && (__cpp_contracts >= 202502L)\n+# define __glibcxx_replaceable_contract_violation_handler 0L\n+# if defined(__glibcxx_want_all) || defined(__glibcxx_want_replaceable_contract_violation_handler)\n+# define __cpp_lib_replaceable_contract_violation_handler 0L\n+# endif\n+# endif\n+#endif /* !defined(__cpp_lib_replaceable_contract_violation_handler) */\n+#undef __glibcxx_want_replaceable_contract_violation_handler\n+\n #if !defined(__cpp_lib_simd)\n # if (__cplusplus > 202302L) && _GLIBCXX_HOSTED && (__cpp_structured_bindings >= 202411L && __cpp_expansion_statements >= 202411L && __SSE2__)\n # define __glibcxx_simd 202506L\ndiff --git a/libstdc++-v3/include/std/contracts b/libstdc++-v3/include/std/contracts\nindex c1fe54750af..a0575fbefd9 100644\n--- a/libstdc++-v3/include/std/contracts\n+++ b/libstdc++-v3/include/std/contracts\n@@ -33,6 +33,7 @@\n #pragma GCC system_header\n \n #define __glibcxx_want_contracts\n+#define __glibcxx_want_replaceable_contract_violation_handler\n #include \n \n #ifdef __cpp_lib_contracts\n","prefixes":[]}