Silence clang static analysis warnings for SetReqLen

This provides a simplified version of the SetReqLen macro when using clang for static analysis. Prior to this change, we would see many Idempotent operation warnings inside this macro due to the common case of calling with arg2 and arg3 being the same variable. This has no effect on code produced during compilation, but it silences a number of false positives in static analysis. XIPassiveGrab.c:170:5: warning: Assigned value is always the same as the existing value SetReqLen(req, num_modifiers, num_modifiers); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from XIPassiveGrab.c:26: .../nx-X11/lib/X11/Xlibint.h:580:8: note: instantiated from: n = badlen; \ ^ Signed-off-by: Jeremy Huddleston <jeremyhu@apple.com> Backported-to-NX-by: Ulrich Sibiller <uli42@gmx.de>

Silence clang static analysis warnings for SetReqLen
c19cda6d · Jeremy Huddleston · Ulrich Sibiller · c300a430 · c19cda6d
Commit c19cda6d authored May 08, 2011 by Jeremy Huddleston Committed by Ulrich Sibiller Oct 19, 2016
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Xlibint.h nx-X11/lib/X11/Xlibint.h +5 -0

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--- a/nx-X11/lib/X11/Xlibint.h
+++ b/nx-X11/lib/X11/Xlibint.h
@@ -558,6 +558,7 @@ extern void *_XGetRequest(Display *dpy, CARD8 type, size_t len);
 * Do not use SetReqLen if "req" does not already have data after the
 * xReq header. req->length must already be >= 2.
 */
+#ifndef __clang_analyzer__
 #define SetReqLen(req,n,badlen) \
    if ((req->length + n) > (unsigned)65535) { \
 	if (dpy->bigreq_size) { \
@@ -568,6 +569,10 @@ extern void *_XGetRequest(Display *dpy, CARD8 type, size_t len);
 	} \
    } else \
 	req->length += n
+#else
+#define SetReqLen(req,n,badlen) \
+    req->length += n
+#endif

 #define SyncHandle() \
 	if (dpy->synchandler) (*dpy->synchandler)(dpy)