[PATCH v2 1/2] diagnostics: Honor #pragma GCC diagnostic in the preprocessor [PR53431]

[Lewis Hyatt via Gcc-patches]

Hello-

I would like please to follow up on this patch submitted for PR53431 here:
https://gcc.gnu.org/pipermail/gcc-patches/2021-December/586191.html

However, it was suggested on the PR that part of it could be split into a
separate simpler patch. I have now done that, and also made a few tweaks to
the first version at the same time, so may I please request that you review
this version 2 instead? This email contains the first smaller cleanup patch,
and the next email contains the main part of it. Thanks very much.

bootstrap and regtest were performed on x86-64 Linux, all tests look the same
before + after, plus the new passing testcases.

FAIL 112 112
PASS 528007 528042
UNSUPPORTED 14888 14888
UNTESTED 132 132
XFAIL 3238 3238
XPASS 17 17

-Lewis

From: Lewis Hyatt <lhy...@gmail.com>
Date: Thu, 23 Dec 2021 17:03:04 -0500
Subject: [PATCH] c++: Minor cleanup in parser.c

The code to determine whether a given token starts a module directive is
currently repeated in 4 places in parser.c. I am about to submit a patch
that needs to add it in a 5th place, so since the code is not completely
trivial (needing to check for 3 different token types), it seems worthwhile
to factor this logic into its own function.

gcc/cp/ChangeLog:

        * parser.c (cp_token_is_module_directive): New function
        refactoring common code.
        (cp_parser_skip_to_closing_parenthesis_1): Use the new function.
        (cp_parser_skip_to_end_of_statement): Likewise.
        (cp_parser_skip_to_end_of_block_or_statement): Likewise.
        (cp_parser_declaration): Likewise.

diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index 33fb40a5b59..9b7446655be 100644
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -629,6 +629,16 @@ cp_lexer_alloc (void)
   return lexer;
 }
 
+/* Return TRUE if token is the start of a module declaration that will be
+   terminated by a CPP_PRAGMA_EOL token.  */
+static inline bool
+cp_token_is_module_directive (cp_token *token)
+{
+  return token->keyword == RID__EXPORT
+    || token->keyword == RID__MODULE
+    || token->keyword == RID__IMPORT;
+}
+
 /* Create a new main C++ lexer, the lexer that gets tokens from the
    preprocessor.  */
 
@@ -3805,9 +3815,7 @@ cp_parser_skip_to_closing_parenthesis_1 (cp_parser 
*parser,
          break;
 
        case CPP_KEYWORD:
-         if (token->keyword != RID__EXPORT
-             && token->keyword != RID__MODULE
-             && token->keyword != RID__IMPORT)
+         if (!cp_token_is_module_directive (token))
            break;
          /* FALLTHROUGH  */
 
@@ -3908,9 +3916,7 @@ cp_parser_skip_to_end_of_statement (cp_parser* parser)
          break;
 
        case CPP_KEYWORD:
-         if (token->keyword != RID__EXPORT
-             && token->keyword != RID__MODULE
-             && token->keyword != RID__IMPORT)
+         if (!cp_token_is_module_directive (token))
            break;
          /* FALLTHROUGH  */
 
@@ -3997,9 +4003,7 @@ cp_parser_skip_to_end_of_block_or_statement (cp_parser* 
parser)
          break;
 
        case CPP_KEYWORD:
-         if (token->keyword != RID__EXPORT
-             && token->keyword != RID__MODULE
-             && token->keyword != RID__IMPORT)
+         if (!cp_token_is_module_directive (token))
            break;
          /* FALLTHROUGH  */
 
@@ -14860,9 +14864,7 @@ cp_parser_declaration (cp_parser* parser, tree 
prefix_attrs)
       else
        cp_parser_module_export (parser);
     }
-  else if (token1->keyword == RID__EXPORT
-          || token1->keyword == RID__IMPORT
-          || token1->keyword == RID__MODULE)
+  else if (cp_token_is_module_directive (token1))
     {
       bool exporting = token1->keyword == RID__EXPORT;
       cp_token *next = exporting ? token2 : token1;