fix: cgo

pkg/analyzer/analyzer.go

@@ -62,6 +62,10 @@ func (r *runner) run(pass *analysis.Pass) (interface{}, error) {
 			return
 		}
 
+		if body == nil {
+			return
+		}
+
 		assignStmt := findNestedContext(pass, node, body.List)
 		if assignStmt == nil {
 			return

pkg/analyzer/analyzer_test.go

@@ -22,6 +22,10 @@ func TestAnalyzer(t *testing.T) {
 			desc: "no func decl",
 			dir:  "no_structpointer",
 		},
+		{
+			desc: "no func decl",
+			dir:  "cgo",
+		},
 		{
 			desc: "func decl",
 			dir:  "common",

pkg/analyzer/testdata/src/cgo/cgo.go

@@ -0,0 +1,51 @@
+package cgo
+
+/*
+ #include <stdio.h>
+ #include <stdlib.h>
+
+ void myprint(char* s) {
+ 	printf("%d\n", s);
+ }
+*/
+import "C"
+
+import (
+	"context"
+	"unsafe"
+)
+
+func _() {
+	cs := C.CString("Hello from stdio\n")
+	C.myprint(cs)
+	C.free(unsafe.Pointer(cs))
+}
+
+func _() {
+	ctx := context.Background()
+
+	for i := 0; i < 10; i++ {
+		ctx := context.WithValue(ctx, "key", i)
+		ctx = context.WithValue(ctx, "other", "val")
+	}
+
+	for i := 0; i < 10; i++ {
+		ctx = context.WithValue(ctx, "key", i) // want "nested context in loop"
+		ctx = context.WithValue(ctx, "other", "val")
+	}
+
+	for item := range []string{"one", "two", "three"} {
+		ctx = wrapContext(ctx) // want "nested context in loop"
+		ctx := context.WithValue(ctx, "key", item)
+		ctx = wrapContext(ctx)
+	}
+
+	for {
+		ctx = wrapContext(ctx) // want "nested context in loop"
+		break
+	}
+}
+
+func wrapContext(ctx context.Context) context.Context {
+	return context.WithoutCancel(ctx)
+}