vala: Transform cast from floating-type to boxed-type

Don't generate invalid c-code leading to "cannot convert to a pointer type"

Fixes https://gitlab.gnome.org/GNOME/vala/issues/991

4 files changed, 40 insertions, 0 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 7a99b0af2..160d77169 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -24,6 +24,7 @@ TESTS = \
 	basic-types/integers.vala \
 	basic-types/escape-chars.vala \
 	basic-types/floats.vala \
+	basic-types/floats-boxed-cast.vala \
 	basic-types/boolean.vala \
 	basic-types/custom-types.vala \
 	basic-types/default-gtype.vala \
@@ -570,6 +571,7 @@ TESTS = \
 	asynchronous/yield.vala \
 	generics/arrays-not-supported.test \
 	generics/constructor-chain-up.vala \
+	generics/floating-type-cast.vala \
 	generics/inference-argument-may-fail.vala \
 	generics/inference-static-function.vala \
 	generics/parameter-sizeof-initializer.vala \
diff --git a/tests/basic-types/floats-boxed-cast.vala b/tests/basic-types/floats-boxed-cast.vala
new file mode 100644
index 000000000..86e9f52cf
--- /dev/null
+++ b/tests/basic-types/floats-boxed-cast.vala
@@ -0,0 +1,7 @@
+void main () {
+	var f = (float?) 23.0f;
+	assert (f == 23.0f);
+
+	var d = (double?) 42.0;
+	assert (d == 42.0);
+}
diff --git a/tests/generics/floating-type-cast.vala b/tests/generics/floating-type-cast.vala
new file mode 100644
index 000000000..9475a4219
--- /dev/null
+++ b/tests/generics/floating-type-cast.vala
@@ -0,0 +1,9 @@
+void foo<G,T> (G g, T t) {
+	assert ((float?) g == 23.0f);
+	assert ((double?) t == 42.0);
+}
+
+void main () {
+	foo ((float?) 23.0f, (double?) 42.0);
+	foo<float?,double?> ((float?) 23.0f, (double?) 42.0);
+}
diff --git a/vala/valacastexpression.vala b/vala/valacastexpression.vala
index d51b4e205..5dc60c726 100644
--- a/vala/valacastexpression.vala
+++ b/vala/valacastexpression.vala
@@ -172,6 +172,28 @@ public class Vala.CastExpression : Expression {
 			}
 		}
 
+		// Implicit transformation of stack-allocated value to heap-allocated boxed-type
+		if (!(is_silent_cast || is_non_null_cast)
+		    && (type_reference is ValueType && type_reference.nullable)
+		    && !inner.value_type.nullable
+		    && inner.value_type is FloatingType) {
+			var local = new LocalVariable (type_reference, get_temp_name (), null, inner.source_reference);
+			var decl = new DeclarationStatement (local, source_reference);
+
+			insert_statement (context.analyzer.insert_block, decl);
+
+			var temp_access = SemanticAnalyzer.create_temp_access (local, target_type);
+			temp_access.formal_target_type = formal_target_type;
+
+			// don't set initializer earlier as this changes parent_node and parent_statement
+			local.initializer = inner;
+			decl.check (context);
+
+			context.analyzer.replaced_nodes.add (this);
+			parent_node.replace_expression (this, temp_access);
+			return temp_access.check (context);
+		}
+
 		value_type = type_reference;
 		value_type.value_owned = inner.value_type.value_owned;
 		value_type.floating_reference = inner.value_type.floating_reference;