diff --git a/CMakeLists.txt b/CMakeLists.txt
index 74c2102b6..5910154ad 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -497,7 +497,7 @@ sdl_glob_sources(
 if(MSVC AND TARGET SDL3-shared)
   if(SDL_CPU_X64)
     enable_language(ASM_MASM)
-    set(asm_src "${SDL3_SOURCE_DIR}/src/stdlib/SDL_mslibc_x64.asm")
+    set(asm_src "${SDL3_SOURCE_DIR}/src/stdlib/SDL_mslibc_x64.masm")
     target_compile_options(SDL3-shared PRIVATE "$<$<COMPILE_LANGUAGE:ASM_MASM>:/nologo>")
     set_property(SOURCE "${asm_src}" PROPERTY LANGUAGE "ASM_MASM")
     target_sources(SDL3-shared PRIVATE "${asm_src}")
diff --git a/VisualC-GDK/SDL/SDL.vcxproj b/VisualC-GDK/SDL/SDL.vcxproj
index 7fe307986..b7b5a72c0 100644
--- a/VisualC-GDK/SDL/SDL.vcxproj
+++ b/VisualC-GDK/SDL/SDL.vcxproj
@@ -733,7 +733,7 @@
     <ClCompile Include="..\..\src\stdlib\SDL_iconv.c" />
     <ClCompile Include="..\..\src\stdlib\SDL_malloc.c" />
     <ClCompile Include="..\..\src\stdlib\SDL_mslibc.c" />
-    <MASM Condition="'$(Platform)'=='x64'" Include="..\..\src\stdlib\SDL_mslibc_x64.asm" >
+    <MASM Condition="'$(Platform)'=='x64'" Include="..\..\src\stdlib\SDL_mslibc_x64.masm" >
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
     </MASM>
     <ClCompile Include="..\..\src\stdlib\SDL_qsort.c" />
diff --git a/VisualC-GDK/SDL/SDL.vcxproj.filters b/VisualC-GDK/SDL/SDL.vcxproj.filters
index 08257eaf3..e9f4d52c5 100644
--- a/VisualC-GDK/SDL/SDL.vcxproj.filters
+++ b/VisualC-GDK/SDL/SDL.vcxproj.filters
@@ -1397,7 +1397,7 @@
     <ClCompile Include="..\..\src\stdlib\SDL_mslibc.c">
       <Filter>stdlib</Filter>
     </ClCompile>
-    <MASM Include="..\..\src\stdlib\SDL_mslibc_x64.asm">
+    <MASM Include="..\..\src\stdlib\SDL_mslibc_x64.masm">
       <Filter>stdlib</Filter>
     </MASM>
     <ClCompile Include="..\..\src\core\gdk\SDL_gdk.cpp">
diff --git a/VisualC-WinRT/SDL-UWP.vcxproj b/VisualC-WinRT/SDL-UWP.vcxproj
index 2e1701a4d..715c60204 100644
--- a/VisualC-WinRT/SDL-UWP.vcxproj
+++ b/VisualC-WinRT/SDL-UWP.vcxproj
@@ -419,7 +419,7 @@
     <ClCompile Include="..\src\stdlib\SDL_iconv.c" />
     <ClCompile Include="..\src\stdlib\SDL_malloc.c" />
     <ClCompile Include="..\src\stdlib\SDL_mslibc.c" />
-    <MASM Condition="'$(Platform)'=='x64'" Include="..\src\stdlib\SDL_mslibc_x64.asm" >
+    <MASM Condition="'$(Platform)'=='x64'" Include="..\src\stdlib\SDL_mslibc_x64.masm" >
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
     </MASM>
     <ClCompile Include="..\src\stdlib\SDL_qsort.c" />
diff --git a/VisualC-WinRT/SDL-UWP.vcxproj.filters b/VisualC-WinRT/SDL-UWP.vcxproj.filters
index d92ce7338..728fdbbcc 100644
--- a/VisualC-WinRT/SDL-UWP.vcxproj.filters
+++ b/VisualC-WinRT/SDL-UWP.vcxproj.filters
@@ -899,7 +899,7 @@
     <ClCompile Include="..\src\stdlib\SDL_mslibc.c">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <MASM Include="..\src\stdlib\SDL_mslibc_x64.asm">
+    <MASM Include="..\src\stdlib\SDL_mslibc_x64.masm">
       <Filter>stdlib</Filter>
     </MASM>
     <ClCompile Include="..\src\core\windows\pch.c">
diff --git a/VisualC/SDL/SDL.vcxproj b/VisualC/SDL/SDL.vcxproj
index 3f38d13f8..0b5345789 100644
--- a/VisualC/SDL/SDL.vcxproj
+++ b/VisualC/SDL/SDL.vcxproj
@@ -613,7 +613,7 @@
     <ClCompile Include="..\..\src\stdlib\SDL_iconv.c" />
     <ClCompile Include="..\..\src\stdlib\SDL_malloc.c" />
     <ClCompile Include="..\..\src\stdlib\SDL_mslibc.c" />
-    <MASM Condition="'$(Platform)'=='x64'" Include="..\..\src\stdlib\SDL_mslibc_x64.asm" >
+    <MASM Condition="'$(Platform)'=='x64'" Include="..\..\src\stdlib\SDL_mslibc_x64.masm" >
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
     </MASM>
     <ClCompile Include="..\..\src\stdlib\SDL_qsort.c" />
diff --git a/VisualC/SDL/SDL.vcxproj.filters b/VisualC/SDL/SDL.vcxproj.filters
index 6002a968c..e53a8eb40 100644
--- a/VisualC/SDL/SDL.vcxproj.filters
+++ b/VisualC/SDL/SDL.vcxproj.filters
@@ -1387,7 +1387,7 @@
     <ClCompile Include="..\..\src\stdlib\SDL_mslibc.c">
       <Filter>stdlib</Filter>
     </ClCompile>
-    <MASM Include="..\..\src\stdlib\SDL_mslibc_x64.asm">
+    <MASM Include="..\..\src\stdlib\SDL_mslibc_x64.masm">
       <Filter>stdlib</Filter>
     </MASM>
   </ItemGroup>
diff --git a/src/stdlib/SDL_mslibc_x64.asm b/src/stdlib/SDL_mslibc_x64.masm
similarity index 100%
rename from src/stdlib/SDL_mslibc_x64.asm
rename to src/stdlib/SDL_mslibc_x64.masm