// - any additional words listed in ctxt.BuildTags
//
// If a file's name, after stripping the extension and a possible _test suffix,
-// matches *_GOOS, *_GOARCH, or *_GOOS_GOARCH for any known operating
-// system and architecture values, then the file is considered to have an implicit
-// build constraint requiring those terms.
+// matches any of the following patterns:
+// *_GOOS
+// *_GOARCH
+// *_GOOS_GOARCH
+// (example: source_windows_amd64.go) or the literals:
+// GOOS
+// GOARCH
+// (example: windows.go) where GOOS and GOARCH represent any known operating
+// system and architecture values respectively, then the file is considered to
+// have an implicit build constraint requiring those terms.
//
// To keep a file from being considered for the build:
//