fix #7596 and #7511: proc literal as union variant in compound literal crashes backend

src/check_expr.cpp

@@ -9527,7 +9527,9 @@ gb_internal bool check_is_operand_compound_lit_constant(CheckerContext *c, Opera
 			return true;
 		}
 		if (expr->kind == Ast_ProcLit) {
-			add_type_and_value(c, expr, Addressing_Constant, type_of_expr(expr), exact_value_procedure(expr));
+			ExactValue value = exact_value_procedure(expr);
+			value.variant_type = o->value.variant_type;
+			add_type_and_value(c, expr, Addressing_Constant, type_of_expr(expr), value);
 			return true;
 		}
 

tests/issues/run.bat

@@ -60,6 +60,7 @@ clang -c ..\test_issue_sysv_abi.c -o test_issue_sysv_abi_c.o || exit /b
 ..\..\..\odin test ..\test_issue_swizzle_multi_assign.odin %COMMON%  || exit /b
 ..\..\..\odin run ..\test_issue_7562.odin %COMMON% -no-crt -no-thread-local || exit /b
 ..\..\..\odin run ..\test_issue_7562.odin %COMMON% -no-crt -no-thread-local -o:speed || exit /b
+..\..\..\odin run ..\test_issue_7596.odin %COMMON% || exit /b
 
 @echo off
 

tests/issues/run.sh

@@ -91,6 +91,7 @@ $ODIN test ../test_issue_7008.odin $COMMON
 $ODIN check ../test_issue_7012.odin -no-entry-point $COMMON_CHECK
 $ODIN build ../test_issue_7037.odin $COMMON -o:none
 $ODIN run ../test_issue_7564.odin $COMMON
+$ODIN run ../test_issue_7596.odin $COMMON
 $ODIN test ../test_issue_7421.odin $COMMON
 if [[ $($ODIN check ../test_issue_7421_tagged_duplicate.odin $COMMON_CHECK 2>&1 >/dev/null | grep -c "Error: Duplicate case") -eq 1 ]]; then
 	echo "SUCCESSFUL 1/1"

tests/issues/test_issue_7596.odin

@@ -0,0 +1,24 @@
+// Tests issue #7596 and #7511: a procedure literal converted to a union variant inside a
+// compound literal crashed the backend with `value_type != nullptr`.
+// https://github.com/odin-lang/Odin/issues/7596
+package test_issues
+
+P :: proc() -> int
+U :: union {P, int}
+S :: struct {
+	u: U,
+	m: Maybe(P),
+}
+
+global_slice := []U{proc() -> int { return 1 }, 2}
+global_struct := S{u = proc() -> int { return 3 }, m = proc() -> int { return 4 }}
+
+main :: proc() {
+	local := [1]U{proc() -> int { return 5 }}
+
+	assert(global_slice[0].(P)() == 1)
+	assert(global_slice[1].(int) == 2)
+	assert(global_struct.u.(P)() == 3)
+	assert(global_struct.m.?() == 4)
+	assert(local[0].(P)() == 5)
+}