diff options
Diffstat (limited to 'gcc/c-common.c')
| -rw-r--r-- | gcc/c-common.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/gcc/c-common.c b/gcc/c-common.c index 0ebb9f1..ee4991a 100644 --- a/gcc/c-common.c +++ b/gcc/c-common.c @@ -1133,6 +1133,7 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands, bool op0_const = true, op1_const = true, op2_const = true; bool op0_const_self = true, op1_const_self = true, op2_const_self = true; bool nowarning = TREE_NO_WARNING (expr); + int unused_p; /* This function is not relevant to C++ because C++ folds while parsing, and may need changes to be correct for C++ when C++ @@ -1308,6 +1309,10 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands, : fold_build2_loc (loc, code, TREE_TYPE (expr), op0, op1); else ret = fold (expr); + if (TREE_OVERFLOW_P (ret) + && !TREE_OVERFLOW_P (op0) + && !TREE_OVERFLOW_P (op1)) + overflow_warning (EXPR_LOCATION (expr), ret); goto out; case INDIRECT_REF: @@ -1342,6 +1347,20 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands, TREE_SIDE_EFFECTS (ret) = TREE_SIDE_EFFECTS (expr); TREE_THIS_VOLATILE (ret) = TREE_THIS_VOLATILE (expr); } + switch (code) + { + case FIX_TRUNC_EXPR: + case FLOAT_EXPR: + CASE_CONVERT: + /* Don't warn about explicit conversions. We will already + have warned about suspect implicit conversions. */ + break; + + default: + if (TREE_OVERFLOW_P (ret) && !TREE_OVERFLOW_P (op0)) + overflow_warning (EXPR_LOCATION (expr), ret); + break; + } goto out; case TRUTH_ANDIF_EXPR: @@ -1351,7 +1370,14 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands, orig_op0 = op0 = TREE_OPERAND (expr, 0); orig_op1 = op1 = TREE_OPERAND (expr, 1); op0 = c_fully_fold_internal (op0, in_init, &op0_const, &op0_const_self); + + unused_p = (op0 == (code == TRUTH_ANDIF_EXPR + ? truthvalue_false_node + : truthvalue_true_node)); + c_inhibit_evaluation_warnings += unused_p; op1 = c_fully_fold_internal (op1, in_init, &op1_const, &op1_const_self); + c_inhibit_evaluation_warnings -= unused_p; + if (op0 != orig_op0 || op1 != orig_op1 || in_init) ret = in_init ? fold_build2_initializer_loc (loc, code, TREE_TYPE (expr), op0, op1) @@ -1380,8 +1406,15 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands, orig_op1 = op1 = TREE_OPERAND (expr, 1); orig_op2 = op2 = TREE_OPERAND (expr, 2); op0 = c_fully_fold_internal (op0, in_init, &op0_const, &op0_const_self); + + c_inhibit_evaluation_warnings += (op0 == truthvalue_false_node); op1 = c_fully_fold_internal (op1, in_init, &op1_const, &op1_const_self); + c_inhibit_evaluation_warnings -= (op0 == truthvalue_false_node); + + c_inhibit_evaluation_warnings += (op0 == truthvalue_true_node); op2 = c_fully_fold_internal (op2, in_init, &op2_const, &op2_const_self); + c_inhibit_evaluation_warnings -= (op0 == truthvalue_true_node); + if (op0 != orig_op0 || op1 != orig_op1 || op2 != orig_op2) ret = fold_build3_loc (loc, code, TREE_TYPE (expr), op0, op1, op2); else |