From 20121b34d856efb59f60e7161417a2bffa63355c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Tue, 9 Oct 2018 06:53:26 +0200
Subject: [PATCH] Fixed #7718 (False positive: out of bounds of already resized
 std::string)

---
 lib/checkbufferoverrun.cpp |  3 +++
 test/testbufferoverrun.cpp | 10 ++++++++++
 2 files changed, 13 insertions(+)

diff --git a/lib/checkbufferoverrun.cpp b/lib/checkbufferoverrun.cpp
index 849e150ff..ccd2fb3cf 100644
--- a/lib/checkbufferoverrun.cpp
+++ b/lib/checkbufferoverrun.cpp
@@ -1561,6 +1561,9 @@ void CheckBufferOverrun::bufferOverrun()
             //  char arr[10] = "123";
             //  arr[7] = 'x'; // warning: arr[7] is inside the array bounds, but past the string's end
 
+            if (tok->valueType() && tok->valueType()->type == ValueType::Type::CONTAINER)
+                continue;
+
             const ArrayInfo arrayInfo(tok->varId(), varname, 1U, Token::getStrSize(strtoken));
             valueFlowCheckArrayIndex(tok->next(), arrayInfo);
         } else {
diff --git a/test/testbufferoverrun.cpp b/test/testbufferoverrun.cpp
index 6d9bda351..0a0ddaafd 100644
--- a/test/testbufferoverrun.cpp
+++ b/test/testbufferoverrun.cpp
@@ -74,6 +74,8 @@ private:
     }
 
     void run() override {
+        LOAD_LIB_2(settings0.library, "std.cfg");
+
         settings0.addEnabled("warning");
         settings0.addEnabled("style");
         settings0.addEnabled("portability");
@@ -3124,6 +3126,14 @@ private:
               "    s[10] = 0;\n"
               "}");
         ASSERT_EQUALS("", errout.str());
+
+        check("void foo()\n" // #7718
+              "{\n"
+              "    std::string s = \"123\";\n"
+              "    s.resize(100);\n"
+              "    s[10] = 0;\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
     }
 
     // data is allocated with alloca