diff --git a/src/V3Coverage.cpp b/src/V3Coverage.cpp
index e24917ecb..8ad8a1bc5 100644
--- a/src/V3Coverage.cpp
+++ b/src/V3Coverage.cpp
@@ -83,10 +83,10 @@ private:
     const char* varIgnoreToggle(AstVar* nodep) {
 	// Return true if this shouldn't be traced
 	// See also similar rule in V3TraceDecl::varIgnoreTrace
-	string prettyName = nodep->prettyName();
 	if (!nodep->isToggleCoverable())
 	    return "Not relevant signal type";
 	if (!v3Global.opt.coverageUnderscore()) {
+	    string prettyName = nodep->prettyName();
 	    if (prettyName[0] == '_')
 	        return "Leading underscore";
 	    if (prettyName.find("._") != string::npos)
diff --git a/src/V3TraceDecl.cpp b/src/V3TraceDecl.cpp
index 391ecf3bc..7a8fb3096 100644
--- a/src/V3TraceDecl.cpp
+++ b/src/V3TraceDecl.cpp
@@ -68,7 +68,6 @@ private:
 	// Return true if this shouldn't be traced
 	// See also similar rule in V3Coverage::varIgnoreToggle
 	AstVar* varp = nodep->varp();
-	string prettyName = varp->prettyName();
 	if (!varp->isTrace()) {
 	    return "Verilator trace_off";
 	}
@@ -76,6 +75,7 @@ private:
 	    return "Verilator cell trace_off";
 	}
 	else if (!v3Global.opt.traceUnderscore()) {
+	    string prettyName = varp->prettyName();
 	    if (prettyName.size()>=1 && prettyName[0] == '_')
 	        return "Leading underscore";
 	    if (prettyName.find("._") != string::npos)