From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2153) id D65803858CDA; Thu, 19 Jan 2023 22:28:18 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D65803858CDA DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1674167298; bh=YJSs+lHhmIQxwCZCCf1OPs0GnVqz2xhcz/SVs6jBnO0=; h=From:To:Subject:Date:From; b=MnE72fao09XqtJRn6+2/xC6GF/Wt4V8uXfoyoHGJzp/q230fr8c1gV2EW4bpFnbFm O7ua5IPntcEo3Z88S1Q4HvtvjyCKsNhMqEgX/ZhhwwK7Dn2PYgoJpPMeLXdGq52EYj t5vVhis5pNkWE2tIlL+A0M7y/Z2Irv7KC2u6Aa/0= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jakub Jelinek To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-5265] c++: Fix up handling of references to anon union members in initializers [PR53932] X-Act-Checkin: gcc X-Git-Author: Jakub Jelinek X-Git-Refname: refs/heads/master X-Git-Oldrev: c81e68a9cdbb5411dce1f1da3b35854212305c7c X-Git-Newrev: 9b9a989adc042b304572fd6d4ade46b47be6ccb8 Message-Id: <20230119222818.D65803858CDA@sourceware.org> Date: Thu, 19 Jan 2023 22:28:18 +0000 (GMT) List-Id: https://gcc.gnu.org/g:9b9a989adc042b304572fd6d4ade46b47be6ccb8 commit r13-5265-g9b9a989adc042b304572fd6d4ade46b47be6ccb8 Author: Jakub Jelinek Date: Thu Jan 19 23:27:34 2023 +0100 c++: Fix up handling of references to anon union members in initializers [PR53932] For anonymous union members we create artificial VAR_DECLs which have DECL_VALUE_EXPR for the actual COMPONENT_REF. That works just fine inside of functions (including global dynamic constructors), because during gimplification such VAR_DECLs are gimplified as their DECL_VALUE_EXPR. This is also done during regimplification. But references to these artificial vars in DECL_INITIAL expressions aren't ever replaced by the DECL_VALUE_EXPRs, so we end up either with link failures like on the testcase below, or worse ICEs with LTO. The following patch fixes those during cp_fully_fold_init where we already walk all the trees (!data->genericize means that function rather than cp_fold_function). 2023-01-19 Jakub Jelinek PR c++/53932 * cp-gimplify.cc (cp_fold_r): During cp_fully_fold_init replace DECL_ANON_UNION_VAR_P VAR_DECLs with their corresponding DECL_VALUE_EXPR. * g++.dg/init/pr53932.C: New test. Diff: --- gcc/cp/cp-gimplify.cc | 10 ++++++++++ gcc/testsuite/g++.dg/init/pr53932.C | 25 +++++++++++++++++++++++++ 2 files changed, 35 insertions(+) diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc index a28215655e7..340b4641046 100644 --- a/gcc/cp/cp-gimplify.cc +++ b/gcc/cp/cp-gimplify.cc @@ -1010,6 +1010,16 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) } break; + case VAR_DECL: + /* In initializers replace anon union artificial VAR_DECLs + with their DECL_VALUE_EXPRs, as nothing will do it later. */ + if (DECL_ANON_UNION_VAR_P (stmt) && !data->genericize) + { + *stmt_p = stmt = unshare_expr (DECL_VALUE_EXPR (stmt)); + break; + } + break; + default: break; } diff --git a/gcc/testsuite/g++.dg/init/pr53932.C b/gcc/testsuite/g++.dg/init/pr53932.C new file mode 100644 index 00000000000..3b129e7d68a --- /dev/null +++ b/gcc/testsuite/g++.dg/init/pr53932.C @@ -0,0 +1,25 @@ +// PR c++/53932 +// { dg-do link } + +static union { int i; }; +int &r = i; +int s = i; +int *t = &i; + +void +foo (int **p, int *q) +{ + static int &u = i; + static int v = i; + static int *w = &i; + int &x = i; + int y = i; + int *z = &i; + *p = &i; + *q = i; +} + +int +main () +{ +}