[TMP]: check ptr.

		Signal: 11 (SEGV)
                Stack trace:
                #0  0x00007febea253c02 __strcmp_avx2 (libc.so.6)
                tibirna#1  0x0000561c9b6cc115 _ZNK5QHashI9ShaStringPK7RevFileE8findNodeERKS0_j (qgit)
                tibirna#2  0x0000561c9b6f5397 _ZN3Git13loadFileNamesEv (qgit)
                tibirna#3  0x00007febea77eac1 _ZN11QMetaObject8activateEP7QObjectiiPPv (libQt5Core.so.5)
                tibirna#4  0x00007febea78bd44 n/a (libQt5Core.so.5)
                tibirna#5  0x00007febea77f495 _ZN7QObject5eventEP6QEvent (libQt5Core.so.5)
                tibirna#6  0x00007febeb10c4e5 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5)
                tibirna#7  0x00007febeb115e11 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5)
                tibirna#8  0x00007febea752d12 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5)
                tibirna#9  0x00007febea7a9ead _ZN14QTimerInfoList14activateTimersEv (libQt5Core.so.5)
                tibirna#10 0x00007febea7aa742 n/a (libQt5Core.so.5)
                tibirna#11 0x00007febe942d3ee g_main_context_dispatch (libglib-2.0.so.0)
                tibirna#12 0x00007febe942f201 n/a (libglib-2.0.so.0)
                tibirna#13 0x00007febe942f241 g_main_context_iteration (libglib-2.0.so.0)
                tibirna#14 0x00007febea7aab13 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5)
                tibirna#15 0x00007febea75183c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5)
                tibirna#16 0x00007febea759676 _ZN16QCoreApplication4execEv (libQt5Core.so.5)
                tibirna#17 0x0000561c9b6b63a1 main (qgit)
                tibirna#18 0x00007febea11e153 __libc_start_main (libc.so.6)
                tibirna#19 0x0000561c9b6b647e _start (qgit)

src/git.cpp

@@ -2541,7 +2541,7 @@ void Git::loadFileNames() {
         QString diffTreeBuf;
         FOREACH (ShaVect, it, revData->revOrder) {
 
-                if (!revsFiles.contains(*it)) {
+                if (!it->isNull() && !revsFiles.contains(*it)) {
                         const Rev* c = revLookup(*it);
                         if (c->parentsCount() == 1) { // skip initials and merges
                                 diffTreeBuf.append(*it).append('\n');