diff --git a/meson.build b/meson.build
index 8d31f5c7..435bd705 100644
--- a/meson.build
+++ b/meson.build
@@ -42,10 +42,11 @@ if buildtype == 'release' or buildtype == 'minsize'
   c_args += '-DNDEBUG'
 endif
 
+message(f'cc_id = @cc_id@')
 if cc_id == 'mvsc'
 
   has_c99_var_decl = cc_version.version_compare('>=18')
-  c_args += '-W3'
+  c_args += '/W3'
 
 elif cc_id == 'clang'