diff options
| -rw-r--r-- | gcc/go/gofrontend/expressions.cc | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/gcc/go/gofrontend/expressions.cc b/gcc/go/gofrontend/expressions.cc index 9d59349..e96ab76 100644 --- a/gcc/go/gofrontend/expressions.cc +++ b/gcc/go/gofrontend/expressions.cc @@ -3055,8 +3055,7 @@ class Type_conversion_expression : public Expression do_lower(Gogo*, Named_object*, Statement_inserter*, int); bool - do_is_constant() const - { return this->expr_->is_constant(); } + do_is_constant() const; bool do_numeric_constant_value(Numeric_constant*) const; @@ -3198,6 +3197,27 @@ Type_conversion_expression::do_lower(Gogo*, Named_object*, return this; } +// Return whether a type conversion is a constant. + +bool +Type_conversion_expression::do_is_constant() const +{ + if (!this->expr_->is_constant()) + return false; + + // A conversion to a type that may not be used as a constant is not + // a constant. For example, []byte(nil). + Type* type = this->type_; + if (type->integer_type() == NULL + && type->float_type() == NULL + && type->complex_type() == NULL + && !type->is_boolean_type() + && !type->is_string_type()) + return false; + + return true; +} + // Return the constant numeric value if there is one. bool |