After r7-987-gf17a223de829cb, the access for the elements of a vector type would lose the qualifiers. So if we had `constvector[0]`, the type of the element of the array would not have const on it. This was due to a missing build_qualified_type for the inner type of the vector when building the array type. We need to add back the call to build_qualified_type and now the access has the correct qualifiers. So the overloads and even if it is a lvalue or rvalue is correctly done.
Note we correctly now reject the testcase gcc.dg/pr83415.c which was incorrectly accepted after r7-987-gf17a223de829cb. Built and tested for aarch64-linux-gnu. PR c++/89224 gcc/c-family/ChangeLog: * c-common.cc (convert_vector_to_array_for_subscript): Call build_qualified_type for the inner type. gcc/cp/ChangeLog: * constexpr.cc (cxx_eval_array_reference): Compare main variants for the vector/array types instead of the types directly. gcc/testsuite/ChangeLog: * g++.dg/torture/vector-subaccess-1.C: New test. * gcc.dg/pr83415.c: Change warning to error. Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com> --- gcc/c-family/c-common.cc | 7 +++++- gcc/cp/constexpr.cc | 3 ++- .../g++.dg/torture/vector-subaccess-1.C | 23 +++++++++++++++++++ gcc/testsuite/gcc.dg/pr83415.c | 2 +- 4 files changed, 32 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/g++.dg/torture/vector-subaccess-1.C diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc index e15eff698df..884dd9043f9 100644 --- a/gcc/c-family/c-common.cc +++ b/gcc/c-family/c-common.cc @@ -8936,6 +8936,7 @@ convert_vector_to_array_for_subscript (location_t loc, if (gnu_vector_type_p (TREE_TYPE (*vecp))) { tree type = TREE_TYPE (*vecp); + tree newitype; ret = !lvalue_p (*vecp); @@ -8950,8 +8951,12 @@ convert_vector_to_array_for_subscript (location_t loc, for function parameters. */ c_common_mark_addressable_vec (*vecp); + /* Make sure qualifiers are copied from the vector type to the new element + of the array type. */ + newitype = build_qualified_type (TREE_TYPE (type), TYPE_QUALS (type)); + *vecp = build1 (VIEW_CONVERT_EXPR, - build_array_type_nelts (TREE_TYPE (type), + build_array_type_nelts (newitype, TYPE_VECTOR_SUBPARTS (type)), *vecp); } diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc index fa346fe01c9..1fe91d16e8e 100644 --- a/gcc/cp/constexpr.cc +++ b/gcc/cp/constexpr.cc @@ -4421,7 +4421,8 @@ cxx_eval_array_reference (const constexpr_ctx *ctx, tree t, if (!lval && TREE_CODE (ary) == VIEW_CONVERT_EXPR && VECTOR_TYPE_P (TREE_TYPE (TREE_OPERAND (ary, 0))) - && TREE_TYPE (t) == TREE_TYPE (TREE_TYPE (TREE_OPERAND (ary, 0)))) + && TYPE_MAIN_VARIANT (TREE_TYPE (t)) + == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (TREE_OPERAND (ary, 0))))) ary = TREE_OPERAND (ary, 0); tree oldidx = TREE_OPERAND (t, 1); diff --git a/gcc/testsuite/g++.dg/torture/vector-subaccess-1.C b/gcc/testsuite/g++.dg/torture/vector-subaccess-1.C new file mode 100644 index 00000000000..0c8958a4e03 --- /dev/null +++ b/gcc/testsuite/g++.dg/torture/vector-subaccess-1.C @@ -0,0 +1,23 @@ +/* PR c++/89224 */ + +/* The access of `vector[i]` has the same qualifiers as the original + vector which was missing. */ + +typedef __attribute__((vector_size(16))) unsigned char Int8x8_t; + +template <class T> +void g(T &x) { + __builtin_abort(); +} +template <class T> +void g(const T &x) { + __builtin_exit(0); +} +void f(const Int8x8_t x) { + g(x[0]); +} +int main(void) +{ + Int8x8_t x ={}; + f(x); +} diff --git a/gcc/testsuite/gcc.dg/pr83415.c b/gcc/testsuite/gcc.dg/pr83415.c index 5934c16d97c..2fc85031505 100644 --- a/gcc/testsuite/gcc.dg/pr83415.c +++ b/gcc/testsuite/gcc.dg/pr83415.c @@ -7,6 +7,6 @@ int main (int argc, short *argv[]) { int i = argc; - y[i] = 7 - i; /* { dg-warning "read-only" } */ + y[i] = 7 - i; /* { dg-error "read-only" } */ return 0; } -- 2.43.0