cmplog_shm shmat was missing result check

docs/Changelog.md

@@ -11,7 +11,10 @@ sending a mail to <afl-users+subscribe@googlegroups.com>.
 
 ### Version ++2.61d (develop):
 
-  - ...
+  - Important fix for memory allocation functions that result in afl-fuzz
+    not identifying crashes - UPDATE!
+  - Small fix for -E/-V to release the CPU
+  - CmpLog does not need sancov anymore
 
 
 ### Version ++2.61c (release):

src/afl-sharedmem.c

@@ -191,7 +191,8 @@ void setup_shm(unsigned char dumb_mode) {
 
   if (cmplog_mode) cmp_map = shmat(cmplog_shm_id, NULL, 0);
 
-  if (!trace_bits) PFATAL("shmat() failed");
+  if (trace_bits == -1 || !trace_bits || cmp_map == -1 || !cmp_map)
+    PFATAL("shmat() failed");
 
 #endif