evaluate: check variadic argument types against format stringformat-check

The variadic argument code did not check any of the variadic arguments
as it did not previously know the possible type. Now we have the possible
formatting information stored in the ctype, we can do some checks on the
printf formatting types.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/sparse.1 b/sparse.1
index 48dab7a9..03ad2141 100644
--- a/sparse.1
+++ b/sparse.1
@@ -257,6 +257,15 @@ Sparse issues these warnings by default.  To turn them off, use
 \fB\-Wno\-external\-function\-has\-definition\fR.
 .
 .TP
+.B \-Wformat
+Warn about parameter mismatch to any variadic function which specifies
+where the format string is specified with the
+.BI __attribute__((format(type, message, va_start)))
+attribute.
+
+Sparse does not issue these warnings by default.
+.
+.TP
 .B \-Winit\-cstring
 Warn about initialization of a char array with a too long constant C string.