From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20243 invoked by alias); 18 Nov 2002 20:46:06 -0000 Mailing-List: contact gcc-prs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-prs-owner@gcc.gnu.org Received: (qmail 20205 invoked by uid 71); 18 Nov 2002 20:46:04 -0000 Date: Sat, 23 Nov 2002 21:36:00 -0000 Message-ID: <20021118204603.20203.qmail@sources.redhat.com> To: neil@gcc.gnu.org Cc: gcc-prs@gcc.gnu.org, From: Neil Booth Subject: Re: preprocessor/8524: _Pragma within macros is improperly expanded Reply-To: Neil Booth X-SW-Source: 2002-11/txt/msg00896.txt.bz2 List-Id: The following reply was made to PR preprocessor/8524; it has been noted by GNATS. From: Neil Booth To: 157416@bugs.debian.org, Andrew Suffield Cc: gcc-gnats@gcc.gnu.org, debian-gcc@lists.debian.org, Zack Weinberg , gcc-patches@gcc.gnu.org Subject: Re: preprocessor/8524: _Pragma within macros is improperly expanded Date: Mon, 18 Nov 2002 20:39:57 +0000 I think this fixes it for good. I'm applying this to 3.3, and 3.2.2 when it arrives. Neil. PR preprocessor/8524 * cpplib.c (run_directive): Remove previous kludge to _Pragma. Add a new one in its place, which hopefully works. (skip_rest_of_line): Change test for bottom-of-context-stack. testsuite: * gcc.dg/cpp/_Pragma5.c: New test. Index: cpplib.c =================================================================== RCS file: /cvs/gcc/gcc/gcc/cpplib.c,v retrieving revision 1.324 diff -u -p -r1.324 cpplib.c --- cpplib.c 22 Sep 2002 02:03:17 -0000 1.324 +++ cpplib.c 17 Nov 2002 22:11:21 -0000 @@ -207,7 +207,7 @@ skip_rest_of_line (pfile) cpp_reader *pfile; { /* Discard all stacked contexts. */ - while (pfile->context != &pfile->base_context) + while (pfile->context->prev) _cpp_pop_context (pfile); /* Sweep up all tokens remaining on the line. */ @@ -1277,9 +1277,6 @@ destringize_and_run (pfile, in) { const unsigned char *src, *limit; char *dest, *result; - cpp_context saved_context; - cpp_context *saved_cur_context; - unsigned int saved_line; dest = result = alloca (in->len + 1); for (src = in->text, limit = src + in->len; src < limit;) @@ -1291,24 +1288,29 @@ destringize_and_run (pfile, in) } *dest = '\0'; - /* FIXME. All this saving is a horrible kludge to handle the case - when we're in a macro expansion. - - A better strategy it to not convert _Pragma to #pragma if doing - preprocessed output, but to just pass it through as-is, unless it - is a CPP pragma in which case is should be processed normally. - When compiling the preprocessed output the _Pragma should be - handled. This will be become necessary when we move to - line-at-a-time lexing since we will be macro-expanding the line - before outputting / compiling it. */ - saved_line = pfile->line; - saved_context = pfile->base_context; - saved_cur_context = pfile->context; - pfile->context = &pfile->base_context; - run_directive (pfile, T_PRAGMA, result, dest - result); - pfile->context = saved_cur_context; - pfile->base_context = saved_context; - pfile->line = saved_line; + /* Ugh; an awful kludge. We are really not set up to be lexing + tokens when in the middle of a macro expansion. Use a new + context to force cpp_get_token to lex, and so skip_rest_of_line + doesn't go beyond the end of the text. Also, remember the + current lexing position so we can return to it later. + + Something like line-at-a-time lexing should remove the need for + this. */ + { + cpp_context *saved_context = pfile->context; + cpp_token *saved_cur_token = pfile->cur_token; + tokenrun *saved_cur_run = pfile->cur_run; + + pfile->context = xnew (cpp_context); + pfile->context->macro = 0; + pfile->context->prev = 0; + run_directive (pfile, T_PRAGMA, result, dest - result); + free (pfile->context); + pfile->context = saved_context; + pfile->cur_token = saved_cur_token; + pfile->cur_run = saved_cur_run; + pfile->line--; + } /* See above comment. For the moment, we'd like