diff --git a/build/moz.configure/toolchain.configure b/build/moz.configure/toolchain.configure
index 8b2416152bd3..288bf483a151 100644
--- a/build/moz.configure/toolchain.configure
+++ b/build/moz.configure/toolchain.configure
@@ -906,5 +906,9 @@ set_define('HAVE_VISIBILITY_ATTRIBUTE',
 set_config('WRAP_SYSTEM_INCLUDES', wrap_system_includes)
 set_config('VISIBILITY_FLAGS', visibility_flags)
 
-include('windows.configure')
+@depends(target, c_compiler)
+def is_windows(target, compiler):
+    return target.kernel == 'WINNT' and compiler.type in ['msvc', 'clang-cl']
+
+include('windows.configure', when=is_windows)
 include('rust.configure')
diff --git a/moz.configure b/moz.configure
index ec90697f5d76..8457d48ebb2e 100644
--- a/moz.configure
+++ b/moz.configure
@@ -278,11 +278,13 @@ system_hunspell = pkg_check_modules('MOZ_HUNSPELL', 'hunspell',
 set_config('MOZ_SYSTEM_HUNSPELL', depends_if(system_hunspell)(lambda _: True))
 
 
-@depends(target)
+@depends(target, c_compiler)
 @imports('os')
-def makensis_progs(target):
+def makensis_progs(target, compiler):
     if target.kernel != 'WINNT':
         return
+    elif target.kernel == 'WINNT' and compiler.type not in ['msvc', 'clang-cl']:
+        return
 
     candidates = [
         'makensis-3.0b3.exe',
diff --git a/old-configure.in b/old-configure.in
index 11a7d5827b39..abf8323889b9 100644
--- a/old-configure.in
+++ b/old-configure.in
@@ -3384,7 +3384,17 @@ if test -n "$MOZ_ANGLE_RENDERER"; then
       AC_MSG_RESULT([Windows SDK not found.])
     fi
   else
-    AC_MSG_ERROR([Couldn't find Windows SDK 8.1 or higher needed for ANGLE.])
+    if test "$target" != "$host"; then
+        case "$target" in
+        *-mingw*)
+            AC_MSG_RESULT([Windows SDK not needed for ANGLE in MinGW build.])
+        ;;
+        *)
+            AC_MSG_ERROR([Couldn't find Windows SDK 8.1 or higher needed for ANGLE.])
+        esac
+    else
+        AC_MSG_ERROR([Couldn't find Windows SDK 8.1 or higher needed for ANGLE.])
+    fi
   fi
 
   if test -z "$MOZ_D3DCOMPILER_VISTA_DLL_PATH"; then