Lower raw string literals

gcc/rust/ChangeLog:

	* hir/rust-ast-lower-base.cc
	(ASTLoweringBase::lower_literal): Lower raw string literals into
	normal string literals.

gcc/testsuite/ChangeLog:

	* rust/compile/issue-3549.rs: New test.

Signed-off-by: Owen Avery <[email protected]>

Author: powerboat9

gcc/rust/hir/rust-ast-lower-base.cc

@@ -933,8 +933,8 @@ ASTLoweringBase::lower_literal (const AST::Literal &literal)
     case AST::Literal::LitType::BYTE_STRING:
       type = HIR::Literal::LitType::BYTE_STRING;
       break;
-    case AST::Literal::LitType::RAW_STRING: // TODO: Lower raw string literals.
-      rust_unreachable ();
+    case AST::Literal::LitType::RAW_STRING:
+      type = HIR::Literal::LitType::STRING;
       break;
     case AST::Literal::LitType::INT:
       type = HIR::Literal::LitType::INT;

gcc/testsuite/rust/compile/issue-3549.rs

@@ -0,0 +1,3 @@
+fn main() {
+    r#""#;
+}