diff --git a/include/verilated.cpp b/include/verilated.cpp
index 4c4836312..2f9d75a49 100644
--- a/include/verilated.cpp
+++ b/include/verilated.cpp
@@ -2412,6 +2412,22 @@ uint64_t vl_time_pow10(int n) {
     return pow10[n];
 }
 
+std::string vl_timescaled_double(double value, const char* format) VL_PURE {
+    const char* suffixp = "s";
+    // clang-format off
+    if      (value >= 1e0)   { suffixp = "s"; value *= 1e0; }
+    else if (value >= 1e-3)  { suffixp = "ms"; value *= 1e3; }
+    else if (value >= 1e-6)  { suffixp = "us"; value *= 1e6; }
+    else if (value >= 1e-9)  { suffixp = "ns"; value *= 1e9; }
+    else if (value >= 1e-12) { suffixp = "ps"; value *= 1e12; }
+    else if (value >= 1e-15) { suffixp = "fs"; value *= 1e15; }
+    else if (value >= 1e-18) { suffixp = "as"; value *= 1e18; }
+    // clang-format on
+    char valuestr[100];
+    VL_SNPRINTF(valuestr, 100, format, value, suffixp);
+    return std::string{valuestr};  // Gets converted to string, so no ref to stack
+}
+
 void VL_PRINTTIMESCALE(const char* namep, const char* timeunitp,
                        const VerilatedContext* contextp) VL_MT_SAFE {
     VL_PRINTF_MT("Time scale of %s is %s / %s\n", namep, timeunitp,
diff --git a/include/verilated_funcs.h b/include/verilated_funcs.h
index f03a59ea8..fe9151a75 100644
--- a/include/verilated_funcs.h
+++ b/include/verilated_funcs.h
@@ -263,7 +263,7 @@ static inline QData VL_EXTENDSIGN_Q(int lbits, QData lhs) VL_PURE {
 extern void _vl_debug_print_w(int lbits, WDataInP const iwp) VL_MT_SAFE;
 
 //=========================================================================
-// Pli macros
+// Time handling
 
 // clang-format off
 
@@ -321,6 +321,8 @@ uint64_t VerilatedContext::time() const VL_MT_SAFE {
 double vl_time_multiplier(int scale) VL_PURE;
 // Return power of 10. e.g. returns 100 if n==2
 uint64_t vl_time_pow10(int n) VL_PURE;
+// Return time as string with timescale suffix
+std::string vl_timescaled_double(double value, const char* format = "%0.0f%s") VL_PURE;
 
 //=========================================================================
 // Functional macros/routines
diff --git a/include/verilated_trace_imp.h b/include/verilated_trace_imp.h
index 0f9de329a..9529a2b66 100644
--- a/include/verilated_trace_imp.h
+++ b/include/verilated_trace_imp.h
@@ -60,22 +60,6 @@ static double timescaleToDouble(const char* unitp) VL_PURE {
     return value;
 }
 
-static std::string doubleToTimescale(double value) VL_PURE {
-    const char* suffixp = "s";
-    // clang-format off
-    if      (value >= 1e0)   { suffixp = "s"; value *= 1e0; }
-    else if (value >= 1e-3)  { suffixp = "ms"; value *= 1e3; }
-    else if (value >= 1e-6)  { suffixp = "us"; value *= 1e6; }
-    else if (value >= 1e-9)  { suffixp = "ns"; value *= 1e9; }
-    else if (value >= 1e-12) { suffixp = "ps"; value *= 1e12; }
-    else if (value >= 1e-15) { suffixp = "fs"; value *= 1e15; }
-    else if (value >= 1e-18) { suffixp = "as"; value *= 1e18; }
-    // clang-format on
-    char valuestr[100];
-    VL_SNPRINTF(valuestr, 100, "%0.0f%s", value, suffixp);
-    return valuestr;  // Gets converted to string, so no ref to stack
-}
-
 //=========================================================================
 // Buffer management
 
@@ -421,7 +405,7 @@ bool VerilatedTrace<VL_SUB_T, VL_BUF_T>::declCode(uint32_t code, const std::stri
 
 template <>
 std::string VerilatedTrace<VL_SUB_T, VL_BUF_T>::timeResStr() const {
-    return doubleToTimescale(m_timeRes);
+    return vl_timescaled_double(m_timeRes);
 }
 
 //=========================================================================
diff --git a/src/V3Os.cpp b/src/V3Os.cpp
index 9286a00d1..92413b62a 100644
--- a/src/V3Os.cpp
+++ b/src/V3Os.cpp
@@ -372,7 +372,9 @@ string V3Os::trueRandom(size_t size) VL_MT_SAFE {
 #if defined(_WIN32) || defined(__MINGW32__)
     const NTSTATUS hr = BCryptGenRandom(nullptr, reinterpret_cast<BYTE*>(data), size,
                                         BCRYPT_USE_SYSTEM_PREFERRED_RNG);
-    if (!BCRYPT_SUCCESS(hr)) v3fatal("Could not acquire random data.");
+    if (VL_UNCOVERABLE(!BCRYPT_SUCCESS(hr))) {
+        v3fatal("Could not acquire random data. Try specifying a key instead.");  // LCOV_EXCL_LINE
+    }
 #else
     std::ifstream is{"/dev/urandom", std::ios::in | std::ios::binary};
     // This read uses the size of the buffer.
@@ -418,7 +420,7 @@ uint64_t V3Os::memUsageBytes() {
 #else
     // Highly unportable. Sorry
     const char* const statmFilename = "/proc/self/statm";
-    FILE* fp = fopen(statmFilename, "r");
+    FILE* const fp = fopen(statmFilename, "r");
     if (!fp) return 0;
     uint64_t size, resident, share, text, lib, data, dt;  // All in pages
     const int items = fscanf(