Fixed build.

src/bgfx.cpp

@@ -1113,22 +1113,26 @@ namespace bgfx
 	{
 		BX_TRACE("");
 
-		BX_TRACE("Detected GPUs (%d):", g_caps.numGPUs);
-		BX_TRACE("\t +----------------   Index");
-		BX_TRACE("\t |  +-------------   Device ID");
-		BX_TRACE("\t |  |    +--------   Vendor ID");
-		for (uint32_t ii = 0; ii < g_caps.numGPUs; ++ii)
-		{
-			const Caps::GPU& gpu = g_caps.gpu[ii];
-
-			BX_TRACE("\t %d: %04x %04x"
-				, ii
-				, gpu.deviceId
-				, gpu.vendorId
-				);
-		}
+		if (0 < g_caps.numGPUs)
+		{
+			BX_TRACE("Detected GPUs (%d):", g_caps.numGPUs);
+			BX_TRACE("\t +----------------   Index");
+			BX_TRACE("\t |  +-------------   Device ID");
+			BX_TRACE("\t |  |    +--------   Vendor ID");
+			for (uint32_t ii = 0; ii < g_caps.numGPUs; ++ii)
+			{
+				const Caps::GPU& gpu = g_caps.gpu[ii];
+				BX_UNUSED(gpu);
 
-		BX_TRACE("");
+				BX_TRACE("\t %d: %04x %04x"
+					, ii
+					, gpu.deviceId
+					, gpu.vendorId
+					);
+			}
+
+			BX_TRACE("");
+		}
 
 		RendererType::Enum renderers[RendererType::Count];
 		uint8_t num = getSupportedRenderers(BX_COUNTOF(renderers), renderers);