Add macros wrapping all usage of gcc's __attribute__.

Until now __attribute__() was defined to be empty for all compilers but
gcc. That's problematic because it prevents using it in other compilers;
which is necessary e.g. for atomics portability.  It's also just
generally dubious to do so in a header as widely included as c.h.

Instead add pg_attribute_format_arg, pg_attribute_printf,
pg_attribute_noreturn macros which are implemented in the compilers that
understand them. Also add pg_attribute_noreturn and pg_attribute_packed,
but don't provide fallbacks, since they can affect functionality.

This means that external code that, possibly unwittingly, relied on
__attribute__ defined to be empty on !gcc compilers may now run into
warnings or errors on those compilers. But there shouldn't be many
occurances of that and it's hard to work around...

Discussion: 54B58BA3.8040302@ohmu.fi
Author: Oskari Saarenmaa, with some minor changes by me.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/bin/pg_dump/pg_backup_tar.c b/src/bin/pg_dump/pg_backup_tar.c
index f48d3696b39..309b4b53dbc 100644
--- a/src/bin/pg_dump/pg_backup_tar.c
+++ b/src/bin/pg_dump/pg_backup_tar.c
@@ -115,7 +115,7 @@ static void tarClose(ArchiveHandle *AH, TAR_MEMBER *TH);
 #ifdef __NOT_USED__
 static char *tarGets(char *buf, size_t len, TAR_MEMBER *th);
 #endif
-static int	tarPrintf(ArchiveHandle *AH, TAR_MEMBER *th, const char *fmt,...) __attribute__((format(PG_PRINTF_ATTRIBUTE, 3, 4)));
+static int	tarPrintf(ArchiveHandle *AH, TAR_MEMBER *th, const char *fmt,...) pg_attribute_printf(3, 4);
 
 static void _tarAddFile(ArchiveHandle *AH, TAR_MEMBER *th);
 static TAR_MEMBER *_tarPositionTo(ArchiveHandle *AH, const char *filename);