Bugfix/cppcheck error code fixes (#244)

* Add flawfinder. Add error code for exit status.

* fix errors found by cppcheck

* fix initialization warning in unit test compile

Co-authored-by: Steve Karg <skarg@users.sourceforge.net>

.github/workflows/lint.yml

@@ -34,6 +34,20 @@ jobs:
         make clean
         make cppcheck
 
+  flawfinder:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v1
+    - name: Create Build Environment
+      run: |
+        sudo apt-get update -qq
+        sudo apt-get install -qq flawfinder
+    - name: cppcheck
+      run: |
+        flawfinder --version
+        make clean
+        make flawfinder
+
   codespell:
     runs-on: ubuntu-latest
     steps: