Handle assert(false) as unreachable, skip assert(true)

1 files changed, 13 insertions, 8 deletions

diff --git a/gcc/gcc/elna-generic.cc b/gcc/gcc/elna-generic.cc
index f4cb3c3..1853e60 100644
--- a/gcc/gcc/elna-generic.cc
+++ b/gcc/gcc/elna-generic.cc
@@ -70,25 +70,30 @@ namespace elna::gcc
                 vec_safe_address(argument_trees));
     }
 
+    // The literal spelling chooses the code generation, so the programmer can ask for
+    // unreachability or for no code at all. A condition that merely folds to a constant
+    // is asserted like any other.
     void generic_visitor::build_assert_builtin(location_t call_location,
             const std::vector<boot::expression *>& arguments)
     {
-        arguments.at(0)->accept(this);
-        tree constant_expression = extract_constant(this->current_expression);
+        boot::literal_expression *const literal = arguments.at(0)->is_literal();
+        const boot::literal<bool> *const condition = literal == nullptr ? nullptr : literal->is_a<bool>();
 
-        if (constant_expression == boolean_false_node)
+        if (condition != nullptr && !condition->value)
         {
             this->current_expression = call_built_in(call_location, "__builtin_unreachable", void_type_node);
         }
-        else if (constant_expression != boolean_true_node)
+        else if (condition != nullptr)
         {
-            tree assert_expression = call_built_in(call_location, "__builtin_trap", void_type_node);
-            this->current_expression = build3(COND_EXPR, void_type_node, this->current_expression,
-                    NULL_TREE, assert_expression);
+            this->current_expression = NULL_TREE;
         }
         else
         {
-            this->current_expression = NULL_TREE;
+            arguments.at(0)->accept(this);
+
+            tree assert_expression = call_built_in(call_location, "__builtin_trap", void_type_node);
+            this->current_expression = build3(COND_EXPR, void_type_node, this->current_expression,
+                    NULL_TREE, assert_expression);
         }
     }