From 5099ca3c8bad6b4853d8cc036235cacb320d2de6 Mon Sep 17 00:00:00 2001
From: Paul Fultz II <pfultz2@yahoo.com>
Date: Tue, 8 Sep 2020 13:14:10 -0500
Subject: [PATCH] Fix issue 9882: segfault in ForwardTraversal (#2785)

---
 lib/valueflow.cpp      | 2 +-
 test/testvalueflow.cpp | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 3ad0072f4..2877fc85b 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -412,7 +412,7 @@ static void setTokenValue(Token* tok, const ValueFlow::Value &value, const Setti
 
     if (value.isContainerSizeValue()) {
         // .empty, .size, +"abc", +'a'
-        if (parent->str() == "+") {
+        if (parent->str() == "+" && parent->astOperand1() && parent->astOperand2()) {
             for (const ValueFlow::Value &value1 : parent->astOperand1()->values()) {
                 for (const ValueFlow::Value &value2 : parent->astOperand2()->values()) {
                     if (value1.path != value2.path)
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 0bd7f70d0..12c1d5cb5 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -4715,6 +4715,15 @@ private:
                "    return x;\n"
                "}\n";
         valueOfTok(code, "x");
+
+        code = "void f() {\n"
+               "    std::string a = b[c->d()];\n"
+               "    if(a.empty()) {\n"
+               "        INFO(std::string{\"a\"} + c->d());\n"
+               "        INFO(std::string{\"b\"} + a);\n"
+               "    }\n"
+               "}\n";
+        valueOfTok(code, "a");
     }
 
     void valueFlowHang() {