From f7d53e269b59c2673b0ecc06c74ec73259eed76e Mon Sep 17 00:00:00 2001
From: zhao-yilun-zyl <dilved1014@gmail.com>
Date: Sun, 28 Jul 2024 22:40:47 +0800
Subject: [PATCH] fix(parser): reset stream position for direct string input

---
 lib/Parser/QasmParser.y | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/Parser/QasmParser.y b/lib/Parser/QasmParser.y
index 538f562..c802403 100644
--- a/lib/Parser/QasmParser.y
+++ b/lib/Parser/QasmParser.y
@@ -384,6 +384,11 @@ int yyparse() {
     if (OQ != "OPENQASM" || OV.empty())
       QASM::ASTOpenQASMVersionTracker::Instance().SetVersion(3.0);
 
+    if (IIS) {
+      IIS->clear();
+      IIS->seekg(0, std::ios::beg);
+    }
+
     if (!QASM::QasmPreprocessor::Instance().Preprocess(IIS)) {
       std::stringstream M;
       M << "OpenQASM Preprocessor failure!";