From 84993d94e13ad2ab3aee151bb5a5e767cf75d51e Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Fri, 11 Feb 2022 13:52:44 +0100 Subject: [PATCH] c++: Fix up constant expression __builtin_convertvector folding [PR104472] The following testcase ICEs, because due to the -frounding-math fold_const_call fails, which is it returns NULL, and returning NULL from cxx_eval* is wrong, all the callers rely on them to either return folded value or original with *non_constant_p = true. The following patch does that, and additionally falls through into the default case where there is diagnostics for the !ctx->quiet case too. 2022-02-11 Jakub Jelinek PR c++/104472 * constexpr.cc (cxx_eval_internal_function) : Only return fold_const_call result if it is non-NULL. Otherwise fall through into the default: case to return t, set *non_constant_p and emit diagnostics if needed. * g++.dg/cpp0x/constexpr-104472.C: New test. --- gcc/cp/constexpr.cc | 9 +++------ gcc/testsuite/g++.dg/cpp0x/constexpr-104472.C | 9 +++++++++ 2 files changed, 12 insertions(+), 6 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp0x/constexpr-104472.C diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc index 9b8e0ec..87f3a7b 100644 --- a/gcc/cp/constexpr.cc +++ b/gcc/cp/constexpr.cc @@ -1840,13 +1840,10 @@ cxx_eval_internal_function (const constexpr_ctx *ctx, tree t, false, non_constant_p, overflow_p); if (TREE_CODE (arg) == VECTOR_CST) - return fold_const_call (CFN_VEC_CONVERT, TREE_TYPE (t), arg); - else - { - *non_constant_p = true; - return t; - } + if (tree r = fold_const_call (CFN_VEC_CONVERT, TREE_TYPE (t), arg)) + return r; } + /* FALLTHRU */ default: if (!ctx->quiet) diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-104472.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-104472.C new file mode 100644 index 0000000..c9c8bf4 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-104472.C @@ -0,0 +1,9 @@ +// PR c++/104472 +// { dg-options "-O2 -frounding-math" } +// { dg-add-options float16 } +// { dg-require-effective-target float16 } + +typedef short __attribute__((__vector_size__ (16))) V; +typedef _Float16 __attribute__((__vector_size__ (16))) F; + +V v = __builtin_convertvector (__builtin_convertvector ((V){5534}, F), V) < 8; -- 2.7.4