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* Re: preprocessor/8524: _Pragma within macros is improperly expanded
@ 2002-11-24 3:25 Neil Booth
0 siblings, 0 replies; 6+ messages in thread
From: Neil Booth @ 2002-11-24 3:25 UTC (permalink / raw)
To: neil; +Cc: gcc-prs
The following reply was made to PR preprocessor/8524; it has been noted by GNATS.
From: Neil Booth <neil@daikokuya.co.uk>
To: 157416@bugs.debian.org, Andrew Suffield <asuffield@debian.org>
Cc: gcc-gnats@gcc.gnu.org, debian-gcc@lists.debian.org,
Zack Weinberg <zack@codesourcery.com>, gcc-patches@gcc.gnu.org
Subject: Re: preprocessor/8524: _Pragma within macros is improperly expanded
Date: Mon, 18 Nov 2002 20:43:38 +0000
Neil Booth wrote:-
> 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.
Oops, the test got lost waiting for CVS.
Neil.
Index: testsuite/gcc.dg/cpp/_Pragma5.c
===================================================================
RCS file: testsuite/gcc.dg/cpp/_Pragma5.c
diff -N testsuite/gcc.dg/cpp/_Pragma5.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ testsuite/gcc.dg/cpp/_Pragma5.c 18 Nov 2002 20:40:43 -0000
@@ -0,0 +1,14 @@
+/* { dg-do preprocess } */
+
+/* Based on Debian GNATS PR 8524. 17 Nov 2002. */
+
+#define ALPHA(A) alpha_ ## A
+#define BETA(B) beta_ ## B
+#define GAMMA(C) _Pragma("moose") ALPHA(C) BETA(C)
+GAMMA(baz);
+
+/*
+ { dg-final { if ![file exists _Pragma5.i] { return } } }
+ { dg-final { if { [grep _Pragma5.i "alpha_baz beta_baz;"] != "" } { return } } }
+ { dg-final { fail "_Pragma5.c: _Pragma in macro" } }
+*/
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: preprocessor/8524: _Pragma within macros is improperly expanded
@ 2002-11-24 3:35 neil
0 siblings, 0 replies; 6+ messages in thread
From: neil @ 2002-11-24 3:35 UTC (permalink / raw)
To: 157416, asuffield, gcc-bugs, gcc-prs, neil
Synopsis: _Pragma within macros is improperly expanded
State-Changed-From-To: open->closed
State-Changed-By: neil
State-Changed-When: Mon Nov 18 12:51:59 2002
State-Changed-Why:
Fixed, I hope. Applied in 3.3, will soon apply in 3.2.2.
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8524
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: preprocessor/8524: _Pragma within macros is improperly expanded
@ 2002-11-23 21:36 Neil Booth
0 siblings, 0 replies; 6+ messages in thread
From: Neil Booth @ 2002-11-23 21:36 UTC (permalink / raw)
To: neil; +Cc: gcc-prs
The following reply was made to PR preprocessor/8524; it has been noted by GNATS.
From: Neil Booth <neil@daikokuya.co.uk>
To: 157416@bugs.debian.org, Andrew Suffield <asuffield@debian.org>
Cc: gcc-gnats@gcc.gnu.org, debian-gcc@lists.debian.org,
Zack Weinberg <zack@codesourcery.com>, 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
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: preprocessor/8524: _Pragma within macros is improperly expanded
@ 2002-11-22 13:26 neil
0 siblings, 0 replies; 6+ messages in thread
From: neil @ 2002-11-22 13:26 UTC (permalink / raw)
To: 157416, asuffield, gcc-bugs, gcc-prs, neil
Synopsis: _Pragma within macros is improperly expanded
State-Changed-From-To: analyzed->open
State-Changed-By: neil
State-Changed-When: Sun Nov 17 14:07:28 2002
State-Changed-Why:
Patch in progress. Let's nail this for good. Other than a rewrite the only possible fix is a kludge, so let's keep our fingers crossed.
(GNATs insists I change state, consider it "analyzed").
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8524
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: preprocessor/8524: _Pragma within macros is improperly expanded
@ 2002-11-10 22:44 neil
0 siblings, 0 replies; 6+ messages in thread
From: neil @ 2002-11-10 22:44 UTC (permalink / raw)
To: 157416, asuffield, gcc-bugs, gcc-prs, neil, nobody
Synopsis: _Pragma within macros is improperly expanded
Responsible-Changed-From-To: unassigned->neil
Responsible-Changed-By: neil
Responsible-Changed-When: Sun Nov 10 22:44:07 2002
Responsible-Changed-Why:
Mine.
State-Changed-From-To: open->analyzed
State-Changed-By: neil
State-Changed-When: Sun Nov 10 22:44:07 2002
State-Changed-Why:
Yah, I'm not entirely surprised; the code in question is not pretty. I'll take another look.
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8524
^ permalink raw reply [flat|nested] 6+ messages in thread
* preprocessor/8524: _Pragma within macros is improperly expanded
@ 2002-11-10 22:36 Matthias Klose
0 siblings, 0 replies; 6+ messages in thread
From: Matthias Klose @ 2002-11-10 22:36 UTC (permalink / raw)
To: gcc-gnats, debian-gcc; +Cc: Zack Weinberg, Neil Booth, Andrew Suffield
>Number: 8524
>Category: preprocessor
>Synopsis: _Pragma within macros is improperly expanded
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Sun Nov 10 22:36:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator: Matthias Klose
>Release: 3.2.1 2002-11-03
>Organization:
>Environment:
System: Linux smile 2.4.18-xfs #1 Tue Mar 12 22:42:02 CET 2002 i686 unknown
Architecture: i686
host: i386-pc-linux-gnu
build: i386-pc-linux-gnu
target: i386-pc-linux-gnu
>Description:
The original report from the Debian BTS, fix applied to head and branch:
aps100@cyclone:~$ cat foo.c
_Pragma("foo"); int y;
#define FOO _Pragma("foo"); int x;
FOO
aps100@cyclone:~$ cpp-3.2 foo.c
# 1 "foo.c"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "foo.c"
# 1 "foo.c"
#pragma foo
# 1 "foo.c"
; int y;
# 3 "foo.c"
#pragma ; int x;foo
The first line is expanded correctly; the third is not (rendering
_Pragma almost completely useless).
Fixed by Neil:
* cpphash.h (FIRST, LAST, CUR, RLIMIT): Fix definitions.
* cpplib.c (destringize_and_run): Kludge around getting
tokens from in-progress macros.
(_cpp_do__Pragma): Simplify. testsuite:
* gcc.dg/cpp/_Pragma4.c: New test.
Bug submitter claims:
Nope, still not right. Here's a new case where it breaks:
aps100@cyclone:~/tmp$ cat foo.c
#define ALPHA(A) alpha_ ## A
#define BETA(B) beta_ ## B
#define GAMMA(C) _Pragma("moose") ALPHA(C) BETA(C)
GAMMA(baz);
aps100@cyclone:~/tmp$ cpp-3.2 foo.c
# 1 "foo.c"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "foo.c"
# 4 "foo.c"
#pragma moose=20
# 4 "foo.c"
alpha_baz beta_alpha_baz;
aps100@cyclone:~/tmp$ cpp-2.95 foo.c
# 1 "foo.c"
_Pragma("moose") alpha_baz beta_baz ;
=3D=3D
Note how beta_baz has become beta_alpha_baz in 3.2. This only happens
when the _Pragma is present, so I presume it's the same bug in another
form.
But wait! It gets better:
aps100@cyclone:~/tmp$ cat foo.c
#define ALPHA
#define BETA(B) beta_ ## B
#define GAMMA(C) _Pragma("moose") ALPHA BETA(C)
GAMMA(baz);
aps100@cyclone:~/tmp$ cpp-3.2 foo.c
# 1 "foo.c"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "foo.c"
# 4 "foo.c"
#pragma moose=20
# 4 "foo.c"
cpp-3.2: Internal error: Aborted (program cpp0)
Please submit a full bug report.
>How-To-Repeat:
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2002-11-18 20:52 UTC | newest]
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2002-11-24 3:25 preprocessor/8524: _Pragma within macros is improperly expanded Neil Booth
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2002-11-24 3:35 neil
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2002-11-22 13:26 neil
2002-11-10 22:44 neil
2002-11-10 22:36 Matthias Klose
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