Silence warning

[Pavel Sanda]

Hi folks,

gcc is emitting
filetools.cpp: In function 'void lyx::support::fileUnlock(int, const char*)':
filetools.cpp:1084:31: warning: ignoring return value of 'int lockf(int, int, 
__off_t)', declared with attribute warn_unused_result [-Wunused-result]

Is it worth to apply this patch to get rid of it? (2.2 stuff only).
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25509

Pavel

diff --git a/src/support/filetools.cpp b/src/support/filetools.cpp
index 0012481..c46c29e 100644
--- a/src/support/filetools.cpp
+++ b/src/support/filetools.cpp
@@ -1081,7 +1081,8 @@ void fileUnlock(int fd, const char * /* lock_file*/)
 {
 #if defined(HAVE_LOCKF)
        if ( fd >= 0) {
-               (void) lockf(fd, F_ULOCK, 0);
+               int dummy __attribute__((unused));
+               dummy = lockf(fd, F_ULOCK, 0);
                close(fd);
        }
 #endif