public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug libstdc++/52040] New: TR1 is not accessible using compiler flags alone
@ 2012-01-29 14:52 potswa at mac dot com
2012-01-29 18:49 ` [Bug libstdc++/52040] " paolo.carlini at oracle dot com
2012-01-29 22:50 ` redi at gcc dot gnu.org
0 siblings, 2 replies; 3+ messages in thread
From: potswa at mac dot com @ 2012-01-29 14:52 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52040
Bug #: 52040
Summary: TR1 is not accessible using compiler flags alone
Classification: Unclassified
Product: gcc
Version: 4.7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: potswa@mac.com
C++ TR1 (N1836) §1.3/3-4 says
3. … Users should be required to take explicit action to have access to library
extensions.
4. It is recommended either that additional declarations in standard headers be
protected with a macro that is not defined by default, or else that all
extended headers, including both new headers and parallel versions of standard
headers with nonstandard declarations, be placed in a separate directory that
is not part of the default search path.
<end quote>
The "explicit action" is left open-ended, but the document suggests that mere
inclusion of a nonstandard header should fail.
GCC interprets the explicit action to be prefixing the header name with "tr1/".
This is a change to source code, whereas other platforms such as MSVC allow TR1
to be used without altering the header names.
An alternative way to use GCC would be to pass "-isystem
/usr/include/c++/.../tr1" — instead of modifying the header name, modify the
search path. This fails because, for example, <tr1/cfloat> includes the line
#include <cfloat>
There are two ways to fix this. One was actually used in some other headers
circa GCC 4.2, and would read:
#include "../cfloat"
The other is perhaps less clean, but opinions may differ:
#include_next <cfloat>
Applying either of these fixes across the tr1/ directory should improve source
compatibility.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug libstdc++/52040] TR1 is not accessible using compiler flags alone
2012-01-29 14:52 [Bug libstdc++/52040] New: TR1 is not accessible using compiler flags alone potswa at mac dot com
@ 2012-01-29 18:49 ` paolo.carlini at oracle dot com
2012-01-29 22:50 ` redi at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: paolo.carlini at oracle dot com @ 2012-01-29 18:49 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52040
Paolo Carlini <paolo.carlini at oracle dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution| |WONTFIX
--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> 2012-01-29 18:28:00 UTC ---
Too late for this. TR1 is in *deep* bugfix only mode.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug libstdc++/52040] TR1 is not accessible using compiler flags alone
2012-01-29 14:52 [Bug libstdc++/52040] New: TR1 is not accessible using compiler flags alone potswa at mac dot com
2012-01-29 18:49 ` [Bug libstdc++/52040] " paolo.carlini at oracle dot com
@ 2012-01-29 22:50 ` redi at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: redi at gcc dot gnu.org @ 2012-01-29 22:50 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52040
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-01-29 22:22:07 UTC ---
We discussed this years ago, GCC's interpretation is valid, WONTFIX.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2012-01-29 22:22 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-01-29 14:52 [Bug libstdc++/52040] New: TR1 is not accessible using compiler flags alone potswa at mac dot com
2012-01-29 18:49 ` [Bug libstdc++/52040] " paolo.carlini at oracle dot com
2012-01-29 22:50 ` redi at gcc dot gnu.org
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).