From 4007b27d05e3daf1eb7f86251e39ddbbba022425 Mon Sep 17 00:00:00 2001
From: Wolfgang Thaller <wolfgang.thaller@gmx.net>
Date: Tue, 4 Jul 2023 23:30:47 +0200
Subject: [PATCH] fix plain C pascal strings

---
 gcc/gcc/c/c-parser.cc | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/gcc/gcc/c/c-parser.cc b/gcc/gcc/c/c-parser.cc
index ddcfc394b7..7e26a035d9 100644
--- a/gcc/gcc/c/c-parser.cc
+++ b/gcc/gcc/c/c-parser.cc
@@ -7340,6 +7340,7 @@ c_parser_string_literal (c_parser *parser, bool translate, bool wide_ok)
   location_t loc, last_tok_loc;
   enum cpp_ttype type;
   tree value, string_tree;
+  bool pascal_string = false;
 
   tok = c_parser_peek_token (parser);
   loc = tok->location;
@@ -7420,11 +7421,23 @@ c_parser_string_literal (c_parser *parser, bool translate, bool wide_ok)
     warning (OPT_Wtraditional,
 	     "traditional C rejects string constant concatenation");
 
+  if (!strncmp((const char*)strs[0].text, "\"\\p", 3))
+    {
+       pascal_string = true;
+       /* replace \p by a valid escape sequence */
+       ((unsigned char*)strs[0].text)[2] = 'n';
+    }
+
   if ((type == CPP_STRING || wide_ok)
       && ((translate
 	  ? cpp_interpret_string : cpp_interpret_string_notranslate)
 	  (parse_in, strs, count, &istr, type)))
     {
+      if (pascal_string)
+        {
+          /* put the real string length in */
+          ((unsigned char*)istr.text)[0] = (unsigned char) (istr.len - 2);
+        }
       value = build_string (istr.len, (const char *) istr.text);
       free (CONST_CAST (unsigned char *, istr.text));
       if (count > 1)
@@ -7475,7 +7488,10 @@ c_parser_string_literal (c_parser *parser, bool translate, bool wide_ok)
     default:
     case CPP_STRING:
     case CPP_UTF8STRING:
-      TREE_TYPE (value) = char_array_type_node;
+      if (pascal_string)
+        TREE_TYPE (value) = uchar_array_type_node;
+      else
+        TREE_TYPE (value) = char_array_type_node;
       break;
     case CPP_STRING16:
       TREE_TYPE (value) = char16_array_type_node;