diff --git a/3rdparty/ocornut-imgui/imgui.cpp b/3rdparty/ocornut-imgui/imgui.cpp
index 2939cd11..9db3eced 100644
--- a/3rdparty/ocornut-imgui/imgui.cpp
+++ b/3rdparty/ocornut-imgui/imgui.cpp
@@ -5548,7 +5548,7 @@ static bool InputTextFilterCharacter(unsigned int* p_char, ImGuiInputTextFlags f
 
         if (flags & ImGuiInputTextFlags_CharsUppercase)
             if (c >= 'a' && c <= 'z')
-                *p_char = (c += unsigned int('A'-'a'));
+                *p_char = (c += (unsigned int)('A'-'a'));
 
         if (flags & ImGuiInputTextFlags_CharsNoBlank)
             if (ImCharIsSpace(c))