diff --git a/SConstruct b/SConstruct
index f8b2d82b660..9783b3eacac 100644
--- a/SConstruct
+++ b/SConstruct
@@ -62,7 +62,7 @@ platform_arg = ARGUMENTS.get("platform", ARGUMENTS.get("p", False))
 if (os.name == "posix"):
     pass
 elif (os.name == "nt"):
-    if (os.getenv("VCINSTALLDIR") == None or platform_arg == "android"):
+    if (os.getenv("VCINSTALLDIR") == None or platform_arg == "android" or platform_arg == "javascript"):
         custom_tools = ['mingw']
 
 env_base = Environment(tools=custom_tools)
@@ -288,7 +288,7 @@ if selected_platform in platform_list:
     if (env["warnings"] == 'yes'):
         print("WARNING: warnings=yes is deprecated; assuming warnings=all")
 
-    if (os.name == "nt" and os.getenv("VSINSTALLDIR")): # MSVC, needs to stand out of course
+    if (os.name == "nt" and os.getenv("VSINSTALLDIR") and (platform_arg == "windows" or platform_arg == "uwp")): # MSVC, needs to stand out of course
         disable_nonessential_warnings = ['/wd4267', '/wd4244', '/wd4305', '/wd4800'] # Truncations, narrowing conversions...
         if (env["warnings"] == 'extra'):
             env.Append(CCFLAGS=['/Wall']) # Implies /W4