On Jan 6, 2015, at 05:24, Ramsay Jones wrote:

On 06/01/15 10:34, Kyle J. McKay wrote:

quoted

Avoid this by adding parentheses around the expansion of the
N_ macro so that instead of ending up with two adjacent strings
that are then combined by the preprocessor, two adjacent strings
surrounded by parentheses result instead which causes a compile
error so the mistake can be quickly found and corrected.

Signed-off-by: Kyle J. McKay <redacted>
---
This patch is optional, but prevents the problem fixed by 1/2
from recurring.

gettext.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gettext.h b/gettext.h
index 7671d09d..d11a4139 100644
--- a/gettext.h
+++ b/gettext.h

@@ -63,6 +63,6 @@ const char *Q_(const char *msgid, const char  

*plu, unsigned long n)
}

/* Mark msgid for translation but do not translate it. */
-#define N_(msgid) msgid
+#define N_(msgid) (msgid)

#endif

Hmm, see commit 642f85faa ("i18n: avoid parenthesized string as
array initializer", 07-04-2011), for a counter-point. :-P

Oh interesting.  So the bug bug fixed by 1/2 must have crept in after  
that change then.

Even clang -ansi -pedantic doesn't seem to complain about this.  And  
("a") is just as much a constant expression as "a".  Are you sure it's  
not just a tcc bug?

In any case, 642f85faa is talking about this:

   static const char ignore_error[] = ("something");

which is assigning a const char * to a const char [].

But builtin/log.c uses this:

   static const char * const builtin_log_usage[] = {("something",  
"else"};

Which is assigning a const char * to a const char * const.

Anyhow, if it breaks some existing compiler that works now, it  
shouldn't be picked up.  But it would sure be nice to have something  
to prevent a recurrence of the bug 1/2 fixes.  Perhaps the (msgid)  
version should be enabled when __GNUC__ is defined -- that should be  
compatible and enough folks use that it would catch such a problem  
early.

-Kyle