diff --git a/ci/build_vcddiff.sh b/ci/build_vcddiff.sh
index eefbf13cd..9a0e8b6da 100755
--- a/ci/build_vcddiff.sh
+++ b/ci/build_vcddiff.sh
@@ -11,8 +11,8 @@ set -e
 
 TMP_DIR=$(mktemp -d)
 
-git -C ${TMP_DIR} clone https://github.com/veripool/vcddiff
+git -C "${TMP_DIR}" clone https://github.com/veripool/vcddiff
 VCDDIFF_DIR=${TMP_DIR}/vcddiff
-git -C ${VCDDIFF_DIR} checkout 5112f88b7ba8818dce9dfb72619e64a1fc19542c
-make -C ${VCDDIFF_DIR}
-sudo cp ${VCDDIFF_DIR}/vcddiff /usr/local/bin
+git -C "${VCDDIFF_DIR}" checkout 5112f88b7ba8818dce9dfb72619e64a1fc19542c
+make -C "${VCDDIFF_DIR}"
+sudo cp "${VCDDIFF_DIR}/vcddiff" /usr/local/bin
diff --git a/src/V3Life.cpp b/src/V3Life.cpp
index b73bf8f05..138518f31 100644
--- a/src/V3Life.cpp
+++ b/src/V3Life.cpp
@@ -459,6 +459,7 @@ public:
     virtual ~LifeVisitor() {
         if (m_lifep) { delete m_lifep; m_lifep = NULL; }
     }
+    VL_UNCOPYABLE(LifeVisitor);
 };
 
 //######################################################################
diff --git a/src/V3PreProc.cpp b/src/V3PreProc.cpp
index 2feca95f7..8df36ba8c 100644
--- a/src/V3PreProc.cpp
+++ b/src/V3PreProc.cpp
@@ -358,7 +358,7 @@ void V3PreProcImp::define(FileLine* fl, const string& name, const string& value,
 }
 
 string V3PreProcImp::removeDefines(const string& text) {
-    string val = "0_never_match";
+    string val;
     string rtnsym = text;
     for (int loopprevent=0; loopprevent<100; loopprevent++) {
         string xsym = rtnsym;
diff --git a/src/V3Task.cpp b/src/V3Task.cpp
index cfd2fd490..80a97c9ac 100644
--- a/src/V3Task.cpp
+++ b/src/V3Task.cpp
@@ -252,6 +252,7 @@ public:
         m_callGraph.dumpDotFilePrefixed("task_call");
     }
     virtual ~TaskStateVisitor() {}
+    VL_UNCOPYABLE(TaskStateVisitor);
 };
 
 //######################################################################
diff --git a/test_regress/t/t_mem_multi_io3.cpp b/test_regress/t/t_mem_multi_io3.cpp
index 30aa58aeb..2108bc73e 100644
--- a/test_regress/t/t_mem_multi_io3.cpp
+++ b/test_regress/t/t_mem_multi_io3.cpp
@@ -20,12 +20,6 @@ int main()
     tb = new VM_PREFIX("tb");
 
     // Just a constructor test
-    bool pass = true;
-
-    if (pass) {
-        VL_PRINTF("*-* All Finished *-*\n");
-    } else {
-        vl_fatal(__FILE__, __LINE__, "top", "Unexpected results from test\n");
-    }
+    VL_PRINTF("*-* All Finished *-*\n");
     return 0;
 }