Add staticcheck tool

vendor/honnef.co/go/tools/staticcheck/sa9009/sa9009.go

@@ -0,0 +1,68 @@
+package sa9009
+
+import (
+	"fmt"
+	"strings"
+
+	"golang.org/x/tools/go/analysis"
+
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "SA9009",
+		Run:      run,
+		Requires: []*analysis.Analyzer{},
+	},
+	Doc: &lint.RawDocumentation{
+		Title: "Ineffectual Go compiler directive",
+		Text: `
+A potential Go compiler directive was found, but is ineffectual as it begins
+with whitespace.`,
+		Since:    "2024.1",
+		Severity: lint.SeverityWarning,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+func run(pass *analysis.Pass) (any, error) {
+	for _, f := range pass.Files {
+		for _, cg := range f.Comments {
+			for _, c := range cg.List {
+				// Compiler directives have to be // comments
+				if !strings.HasPrefix(c.Text, "//") {
+					continue
+				}
+				if pass.Fset.PositionFor(c.Pos(), false).Column != 1 {
+					// Compiler directives have to be top-level. This also
+					// avoids a false positive for
+					// 'import _ "unsafe" // go:linkname'
+					continue
+				}
+				text := strings.TrimLeft(c.Text[2:], " \t")
+				if len(text) == len(c.Text[2:]) {
+					// There was no leading whitespace
+					continue
+				}
+				if !strings.HasPrefix(text, "go:") {
+					// Not an attempted compiler directive
+					continue
+				}
+				text = text[3:]
+				if len(text) == 0 || text[0] < 'a' || text[0] > 'z' {
+					// A letter other than a-z after "go:", so unlikely to be an
+					// attempted compiler directive
+					continue
+				}
+				report.Report(pass, c,
+					fmt.Sprintf(
+						"ineffectual compiler directive due to extraneous space: %q",
+						c.Text))
+			}
+		}
+	}
+	return nil, nil
+}