From cf52ee098ac68be768203a4ab1c77b768b03fa7e Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Fri, 2 Sep 2022 07:51:10 +0200
Subject: [PATCH] Fix checkLibraryFunction FPs (#4423)

* Fix checkLibraryFunction FPs

* Fix FP with fclose()

* Format

* Fix FP with reinterpret_cast
---
 lib/checkfunctions.cpp   |  6 ++++++
 lib/checkleakautovar.cpp | 14 ++++++++++----
 test/testfunctions.cpp   |  9 +++++++++
 test/testleakautovar.cpp | 18 ++++++++++++++++++
 4 files changed, 43 insertions(+), 4 deletions(-)

diff --git a/lib/checkfunctions.cpp b/lib/checkfunctions.cpp
index d9321a7c7..56476a442 100644
--- a/lib/checkfunctions.cpp
+++ b/lib/checkfunctions.cpp
@@ -621,6 +621,9 @@ void CheckFunctions::checkLibraryMatchFunctions()
         if (tok->function())
             continue;
 
+        if (Token::simpleMatch(tok->astTop(), "throw"))
+            continue;
+
         if (!mSettings->library.isNotLibraryFunction(tok))
             continue;
 
@@ -631,6 +634,9 @@ void CheckFunctions::checkLibraryMatchFunctions()
         if (mSettings->library.functions.find(functionName) != mSettings->library.functions.end())
             continue;
 
+        if (mSettings->library.podtype(tok->expressionString()))
+            continue;
+
         const Token* start = tok;
         while (Token::Match(start->tokAt(-2), "%name% ::"))
             start = start->tokAt(-2);
diff --git a/lib/checkleakautovar.cpp b/lib/checkleakautovar.cpp
index a9c0bb14a..06efba232 100644
--- a/lib/checkleakautovar.cpp
+++ b/lib/checkleakautovar.cpp
@@ -777,7 +777,7 @@ const Token * CheckLeakAutoVar::checkTokenInsideExpression(const Token * const t
                     rhs = rhs->astParent();
                 }
                 while (rhs->isCast()) {
-                    rhs = rhs->astOperand1();
+                    rhs = rhs->astOperand2() ? rhs->astOperand2() : rhs->astOperand1();
                 }
                 if (rhs->varId() == tok->varId()) {
                     // simple assignment
@@ -814,7 +814,7 @@ const Token * CheckLeakAutoVar::checkTokenInsideExpression(const Token * const t
         if (returnValue.compare(0, 3, "arg") == 0)
             // the function returns one of its argument, we need to process a potential assignment
             return openingPar;
-        return openingPar->link();
+        return isCPPCast(tok->astParent()) ? openingPar : openingPar->link();
     }
 
     return nullptr;
@@ -917,8 +917,14 @@ void CheckLeakAutoVar::functionCall(const Token *tokName, const Token *tokOpenin
             const bool isnull = arg->hasKnownIntValue() && arg->values().front().intvalue == 0;
 
             // Is variable allocated?
-            if (!isnull && (!af || af->arg == argNr))
-                changeAllocStatus(varInfo, allocation, tokName, arg);
+            if (!isnull && (!af || af->arg == argNr)) {
+                const Library::AllocFunc* deallocFunc = mSettings->library.getDeallocFuncInfo(tokName);
+                VarInfo::AllocInfo dealloc(deallocFunc ? deallocFunc->groupId : 0, VarInfo::DEALLOC, tokName);
+                if (dealloc.type == 0)
+                    changeAllocStatus(varInfo, allocation, tokName, arg);
+                else
+                    changeAllocStatus(varInfo, dealloc, tokName, arg);
+            }
         }
         // Check smart pointer
         else if (Token::Match(arg, "%name% < %type%") && mSettings->library.isSmartPointer(argTypeStartTok)) {
diff --git a/test/testfunctions.cpp b/test/testfunctions.cpp
index 22599425b..a59062712 100644
--- a/test/testfunctions.cpp
+++ b/test/testfunctions.cpp
@@ -1831,9 +1831,18 @@ private:
               "}\n");
         ASSERT_EQUALS("", errout.str());
 
+        check("void f(std::uint64_t& u) {\n"
+              "    u = std::uint32_t(u) * std::uint64_t(100);\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
+
         check("void f() { throw(1); }\n"); // #8958
         ASSERT_EQUALS("", errout.str());
 
+        check("using namespace std;\n"
+              "void f() { throw range_error(\"abc\"); }\n");
+        ASSERT_EQUALS("", errout.str());
+
         check("class C {\n" // #9002
               "public:\n"
               "    static int f() { return 1; }\n"
diff --git a/test/testleakautovar.cpp b/test/testleakautovar.cpp
index 1a3c68211..6703a6a1c 100644
--- a/test/testleakautovar.cpp
+++ b/test/testleakautovar.cpp
@@ -2432,6 +2432,24 @@ private:
               "    asm goto(\"assembler code\");\n"
               "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        check("void f() {\n"
+              "    FILE* p = fopen(\"abc.txt\", \"r\");\n"
+              "    if (fclose(p) != 0) {}\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
+
+        check("struct S;\n"
+              "void f(int a, int b, S*& p) {\n"
+              "    if (a == -1) {\n"
+              "        FILE* file = fopen(\"abc.txt\", \"r\");\n"
+              "    }\n"
+              "    if (b) {\n"
+              "        void* buf = malloc(10);\n"
+              "        p = reinterpret_cast<S*>(buf);\n"
+              "    }\n"
+              "}\n", /*cpp*/ true);
+        ASSERT_EQUALS("[test.cpp:5]: (error) Resource leak: file\n", errout.str());
     }
 
     void ptrptr() {