diff --git a/src/common/Platform_mac.cpp b/src/common/Platform_mac.cpp
index b587c01f..4e4aa0ad 100644
--- a/src/common/Platform_mac.cpp
+++ b/src/common/Platform_mac.cpp
@@ -40,15 +40,20 @@
 
 char *Platform::createUserAgent()
 {
-    const size_t max = 160;
+    constexpr const size_t max = 256;
 
-    char *buf = new char[max];
+    char *buf = new char[max]();
+    int length = snprintf(buf, max, "%s/%s (Macintosh; Intel Mac OS X) libuv/%s", APP_NAME, APP_VERSION, uv_version_string());
 
 #   ifdef XMRIG_NVIDIA_PROJECT
     const int cudaVersion = cuda_get_runtime_version();
-    snprintf(buf, max, "%s/%s (Macintosh; Intel Mac OS X) libuv/%s CUDA/%d.%d clang/%d.%d.%d", APP_NAME, APP_VERSION, uv_version_string(), cudaVersion / 1000, cudaVersion % 100, __clang_major__, __clang_minor__, __clang_patchlevel__);
-#   else
-    snprintf(buf, max, "%s/%s (Macintosh; Intel Mac OS X) libuv/%s clang/%d.%d.%d", APP_NAME, APP_VERSION, uv_version_string(), __clang_major__, __clang_minor__, __clang_patchlevel__);
+    length += snprintf(buf + length, max - length, " CUDA/%d.%d", cudaVersion / 1000, cudaVersion % 100);
+#   endif
+
+#   ifdef __clang__
+    length += snprintf(buf + length, max - length, " clang/%d.%d.%d", __clang_major__, __clang_minor__, __clang_patchlevel__);
+#   elif defined(__GNUC__)
+    length += snprintf(buf + length, max - length, " gcc/%d.%d.%d", __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
 #   endif
 
     return buf;
diff --git a/src/common/Platform_unix.cpp b/src/common/Platform_unix.cpp
index 1263b846..901df4be 100644
--- a/src/common/Platform_unix.cpp
+++ b/src/common/Platform_unix.cpp
@@ -54,9 +54,9 @@ typedef cpuset_t cpu_set_t;
 
 char *Platform::createUserAgent()
 {
-    const size_t max = 160;
+    constexpr const size_t max = 256;
 
-    char *buf = new char[max];
+    char *buf = new char[max]();
     int length = snprintf(buf, max, "%s/%s (Linux ", APP_NAME, APP_VERSION);
 
 #   if defined(__x86_64__)
@@ -70,7 +70,9 @@ char *Platform::createUserAgent()
     length += snprintf(buf + length, max - length, " CUDA/%d.%d", cudaVersion / 1000, cudaVersion % 100);
 #   endif
 
-#   ifdef __GNUC__
+#   ifdef __clang__
+    length += snprintf(buf + length, max - length, " clang/%d.%d.%d", __clang_major__, __clang_minor__, __clang_patchlevel__);
+#   elif defined(__GNUC__)
     length += snprintf(buf + length, max - length, " gcc/%d.%d.%d", __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
 #   endif
 
diff --git a/src/common/Platform_win.cpp b/src/common/Platform_win.cpp
index d220f58d..3fa7ea9a 100644
--- a/src/common/Platform_win.cpp
+++ b/src/common/Platform_win.cpp
@@ -63,9 +63,9 @@ static inline OSVERSIONINFOEX winOsVersion()
 char *Platform::createUserAgent()
 {
     const auto osver = winOsVersion();
-    const size_t max = 160;
+    constexpr const size_t max = 256;
 
-    char *buf = new char[max];
+    char *buf = new char[max]();
     int length = snprintf(buf, max, "%s/%s (Windows NT %lu.%lu", APP_NAME, APP_VERSION, osver.dwMajorVersion, osver.dwMinorVersion);
 
 #   if defined(__x86_64__) || defined(_M_AMD64)