From: Jakub Jelinek Date: Thu, 29 Oct 2020 15:27:01 +0000 (+0100) Subject: c++: Diagnose constexpr delete [] new int; and delete new int[N]; [PR95808] X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=815baade9a07d361b1daa1dcfbbda2a79f3ebb52;p=gcc.git c++: Diagnose constexpr delete [] new int; and delete new int[N]; [PR95808] This patch diagnoses delete [] new int; and delete new int[1]; in constexpr contexts by remembering IDENTIFIER_OVL_OP_FLAGS (DECL_NAME (fun)) & OVL_OP_FLAG_VEC from the operator new and checking it at operator delete time. 2020-10-29 Jakub Jelinek PR c++/95808 * cp-tree.h (enum cp_tree_index): Add CPTI_HEAP_VEC_UNINIT_IDENTIFIER and CPTI_HEAP_VEC_IDENTIFIER. (heap_vec_uninit_identifier, heap_vec_identifier): Define. * decl.c (initialize_predefined_identifiers): Initialize those identifiers. * constexpr.c (cxx_eval_call_expression): Reject array allocations deallocated with non-array deallocation or non-array allocations deallocated with array deallocation. (non_const_var_error): Handle heap_vec_uninit_identifier and heap_vec_identifier too. (cxx_eval_constant_expression): Handle also heap_vec_uninit_identifier and in that case during initialization replace it with heap_vec_identifier. (find_heap_var_refs): Handle heap_vec_uninit_identifier and heap_vec_identifier too. * g++.dg/cpp2a/constexpr-new15.C: New test. --- diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c index 7ebdd308dcd..37c836a8a7b 100644 --- a/gcc/cp/constexpr.c +++ b/gcc/cp/constexpr.c @@ -2288,7 +2288,11 @@ cxx_eval_call_expression (const constexpr_ctx *ctx, tree t, { tree type = build_array_type_nelts (char_type_node, tree_to_uhwi (arg0)); - tree var = build_decl (loc, VAR_DECL, heap_uninit_identifier, + tree var = build_decl (loc, VAR_DECL, + (IDENTIFIER_OVL_OP_FLAGS (DECL_NAME (fun)) + & OVL_OP_FLAG_VEC) + ? heap_vec_uninit_identifier + : heap_uninit_identifier, type); DECL_ARTIFICIAL (var) = 1; TREE_STATIC (var) = 1; @@ -2306,6 +2310,42 @@ cxx_eval_call_expression (const constexpr_ctx *ctx, tree t, if (DECL_NAME (var) == heap_uninit_identifier || DECL_NAME (var) == heap_identifier) { + if (IDENTIFIER_OVL_OP_FLAGS (DECL_NAME (fun)) + & OVL_OP_FLAG_VEC) + { + if (!ctx->quiet) + { + error_at (loc, "array deallocation of object " + "allocated with non-array " + "allocation"); + inform (DECL_SOURCE_LOCATION (var), + "allocation performed here"); + } + *non_constant_p = true; + return t; + } + DECL_NAME (var) = heap_deleted_identifier; + ctx->global->values.remove (var); + ctx->global->heap_dealloc_count++; + return void_node; + } + else if (DECL_NAME (var) == heap_vec_uninit_identifier + || DECL_NAME (var) == heap_vec_identifier) + { + if ((IDENTIFIER_OVL_OP_FLAGS (DECL_NAME (fun)) + & OVL_OP_FLAG_VEC) == 0) + { + if (!ctx->quiet) + { + error_at (loc, "non-array deallocation of " + "object allocated with array " + "allocation"); + inform (DECL_SOURCE_LOCATION (var), + "allocation performed here"); + } + *non_constant_p = true; + return t; + } DECL_NAME (var) = heap_deleted_identifier; ctx->global->values.remove (var); ctx->global->heap_dealloc_count++; @@ -4605,7 +4645,9 @@ non_const_var_error (location_t loc, tree r) auto_diagnostic_group d; tree type = TREE_TYPE (r); if (DECL_NAME (r) == heap_uninit_identifier - || DECL_NAME (r) == heap_identifier) + || DECL_NAME (r) == heap_identifier + || DECL_NAME (r) == heap_vec_uninit_identifier + || DECL_NAME (r) == heap_vec_identifier) { error_at (loc, "the content of uninitialized storage is not usable " "in a constant expression"); @@ -6365,8 +6407,10 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx, tree t, && TREE_TYPE (op) == ptr_type_node && TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR && VAR_P (TREE_OPERAND (TREE_OPERAND (op, 0), 0)) - && DECL_NAME (TREE_OPERAND (TREE_OPERAND (op, 0), - 0)) == heap_uninit_identifier) + && (DECL_NAME (TREE_OPERAND (TREE_OPERAND (op, 0), + 0)) == heap_uninit_identifier + || DECL_NAME (TREE_OPERAND (TREE_OPERAND (op, 0), + 0)) == heap_vec_uninit_identifier)) { tree var = TREE_OPERAND (TREE_OPERAND (op, 0), 0); tree var_size = TYPE_SIZE_UNIT (TREE_TYPE (var)); @@ -6380,7 +6424,9 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx, tree t, elt_type = TREE_TYPE (TREE_TYPE (fld2)); cookie_size = TYPE_SIZE_UNIT (TREE_TYPE (fld1)); } - DECL_NAME (var) = heap_identifier; + DECL_NAME (var) + = (DECL_NAME (var) == heap_uninit_identifier + ? heap_identifier : heap_vec_identifier); TREE_TYPE (var) = build_new_constexpr_heap_type (elt_type, cookie_size, var_size); @@ -6651,6 +6697,8 @@ find_heap_var_refs (tree *tp, int *walk_subtrees, void */*data*/) if (VAR_P (*tp) && (DECL_NAME (*tp) == heap_uninit_identifier || DECL_NAME (*tp) == heap_identifier + || DECL_NAME (*tp) == heap_vec_uninit_identifier + || DECL_NAME (*tp) == heap_vec_identifier || DECL_NAME (*tp) == heap_deleted_identifier)) return *tp; diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 4f9038eb201..20774f82620 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -178,6 +178,8 @@ enum cp_tree_index CPTI_HEAP_UNINIT_IDENTIFIER, CPTI_HEAP_IDENTIFIER, CPTI_HEAP_DELETED_IDENTIFIER, + CPTI_HEAP_VEC_UNINIT_IDENTIFIER, + CPTI_HEAP_VEC_IDENTIFIER, CPTI_LANG_NAME_C, CPTI_LANG_NAME_CPLUSPLUS, @@ -322,6 +324,8 @@ extern GTY(()) tree cp_global_trees[CPTI_MAX]; #define heap_uninit_identifier cp_global_trees[CPTI_HEAP_UNINIT_IDENTIFIER] #define heap_identifier cp_global_trees[CPTI_HEAP_IDENTIFIER] #define heap_deleted_identifier cp_global_trees[CPTI_HEAP_DELETED_IDENTIFIER] +#define heap_vec_uninit_identifier cp_global_trees[CPTI_HEAP_VEC_UNINIT_IDENTIFIER] +#define heap_vec_identifier cp_global_trees[CPTI_HEAP_VEC_IDENTIFIER] #define lang_name_c cp_global_trees[CPTI_LANG_NAME_C] #define lang_name_cplusplus cp_global_trees[CPTI_LANG_NAME_CPLUSPLUS] diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c index ee3c353935d..39f56b81275 100644 --- a/gcc/cp/decl.c +++ b/gcc/cp/decl.c @@ -4245,6 +4245,8 @@ initialize_predefined_identifiers (void) {"heap uninit", &heap_uninit_identifier, cik_normal}, {"heap ", &heap_identifier, cik_normal}, {"heap deleted", &heap_deleted_identifier, cik_normal}, + {"heap [] uninit", &heap_vec_uninit_identifier, cik_normal}, + {"heap []", &heap_vec_identifier, cik_normal}, {NULL, NULL, cik_normal} }; diff --git a/gcc/testsuite/g++.dg/cpp2a/constexpr-new15.C b/gcc/testsuite/g++.dg/cpp2a/constexpr-new15.C new file mode 100644 index 00000000000..e97e7aa6a6a --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/constexpr-new15.C @@ -0,0 +1,21 @@ +// PR c++/95808 +// { dg-do compile { target c++20 } } + +constexpr +bool foo () +{ + int *p = new int; // { dg-message "allocation performed here" } + delete[] p; // { dg-error "array deallocation of object allocated with non-array allocation" } + return false; +} + +constexpr +bool bar () +{ + int *p = new int[1]; // { dg-message "allocation performed here" } + delete p; // { dg-error "non-array deallocation of object allocated with array allocation" } + return false; +} + +constexpr auto x = foo (); +constexpr auto y = bar ();