Commit Graph

14 Commits

Author SHA1 Message Date
Peter Eisentraut
0cb1fac3b1 Add noreturn attributes to some error reporting functions 2013-02-12 07:13:22 -05:00
Tom Lane
b853eb9718 Improve handling of ereport(ERROR) and elog(ERROR).
In commit 71450d7fd6, we added code to inform
suitably-intelligent compilers that ereport() doesn't return if the elevel
is ERROR or higher.  This patch extends that to elog(), and also fixes a
double-evaluation hazard that the previous commit created in ereport(),
as well as reducing the emitted code size.

The elog() improvement requires the compiler to support __VA_ARGS__, which
should be available in just about anything nowadays since it's required by
C99.  But our minimum language baseline is still C89, so add a configure
test for that.

The previous commit assumed that ereport's elevel could be evaluated twice,
which isn't terribly safe --- there are already counterexamples in xlog.c.
On compilers that have __builtin_constant_p, we can use that to protect the
second test, since there's no possible optimization gain if the compiler
doesn't know the value of elevel.  Otherwise, use a local variable inside
the macros to prevent double evaluation.  The local-variable solution is
inferior because (a) it leads to useless code being emitted when elevel
isn't constant, and (b) it increases the optimization level needed for the
compiler to recognize that subsequent code is unreachable.  But it seems
better than not teaching non-gcc compilers about unreachability at all.

Lastly, if the compiler has __builtin_unreachable(), we can use that
instead of abort(), resulting in a noticeable code savings since no
function call is actually emitted.  However, it seems wise to do this only
in non-assert builds.  In an assert build, continue to use abort(), so that
the behavior will be predictable and debuggable if the "impossible"
happens.

These changes involve making the ereport and elog macros emit do-while
statement blocks not just expressions, which forces small changes in
a few call sites.

Andres Freund, Tom Lane, Heikki Linnakangas
2013-01-13 18:40:09 -05:00
Tom Lane
2e95f1f002 Add "%option warn" to all flex input files that lacked it.
This is recommended in the flex manual, and there seems no good reason
not to use it everywhere.
2011-08-25 13:55:57 -04:00
Peter Eisentraut
fc946c39ae Remove useless whitespace at end of lines 2010-11-23 22:34:55 +02:00
Tom Lane
3e4264ca35 Add %option noinput to contrib's flex scanners, to suppress gcc 4.3
warnings.  Peter did this for core awhile ago but evidently missed
contrib.
2008-08-25 23:12:45 +00:00
Tom Lane
ad148c4154 Suppress warnings on platforms where fprintf is a macro (eg, recent
Fedora).  This was already done by somebody for the core flex files,
but these contrib files seem to have been missed.
2005-10-15 20:37:36 +00:00
Tom Lane
db64df4b1c Fix contrib/cube and contrib/seg to compile on Windows.
Andreas Pflug
2004-09-14 04:21:38 +00:00
Tom Lane
fa96a5e15b Add %option nodefault to all our flex lexers. Fix a couple of rule gaps
exposed thereby.  AFAICT these would not lead to any worse problems than
junk emitted on the backend's stdout, but we should have the option to
catch possible worse errors in future.
2004-02-24 22:06:32 +00:00
Tom Lane
043be9ad96 Make contrib/seg work with flex 2.5.31. Fix it up to have a real
btree operator class, too, since in PG 7.4 you can't GROUP without one.
2003-09-14 02:18:49 +00:00
Tom Lane
5666462f2e Ensure that in all flex lexers that are part of the backend, a
yy_fatal_error() call results in elog(ERROR) not exit().  This was
already fixed in the main lexer and plpgsql, but extend same technique
to all the other dot-l files.  Also, on review of the possible calls
to yy_fatal_error(), it seems safe to use elog(ERROR) not elog(FATAL).
2003-05-29 22:30:02 +00:00
Tom Lane
df7201c3c5 Remove no-longer-needed inclusions to improve backward compatibility
with older bison versions.
2002-11-07 06:06:17 +00:00
Tom Lane
52c9d25933 Be careful to include postgres.h *before* any system headers, to ensure
that the right flavors of largefile-related definitions are seen.
Most of these changes are probably unnecessary, but better safe than
sorry.
2002-09-05 00:43:07 +00:00
Tom Lane
9f1fc1080e Since we're depending on %option noyywrap in the main scanner now,
we may as well use it in all our flex files.  Make all the flex files
have a consistent set of options.
2002-07-30 16:33:08 +00:00
Tom Lane
a3694b420f Gene Selkov's SEG datatype (GiST example code) 2000-12-11 20:40:33 +00:00