llcppsigfetch:json memory free

chore/_xtool/llcppsigfetch/parse/cvt_test/cvt.go

@@ -2,6 +2,7 @@ package cvttest
 
 import (
 	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/c/cjson"
 	"github.com/goplus/llgo/chore/_xtool/llcppsigfetch/parse"
 )
 
@@ -20,9 +21,12 @@ func RunTest(testName string, testCases []string) {
 			panic(err)
 		}
 
-		json := converter.MarshalASTFiles()
-		c.Printf(c.Str("%s Case %d:\n%s\n\n"), c.AllocaCStr(testName), c.Int(i+1), json.Print())
+		result := converter.MarshalASTFiles()
+		str := result.Print()
+		c.Printf(c.Str("%s Case %d:\n%s\n\n"), c.AllocaCStr(testName), c.Int(i+1), str)
 
+		cjson.FreeCStr(str)
+		result.Delete()
 		converter.Dispose()
 	}
 }