From: Gabor Horvath <xazax.hun@gmail.com>
Date: Sat, 10 Aug 2019 00:32:29 +0000 (+0000)
Subject: Fix a false positive warning when initializing members with gsl::Owners.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=bc619fcd33a27e82817954cd708cc7724c09b155;p=clang

Fix a false positive warning when initializing members with gsl::Owners.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@368501 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index a54f5dbd75..9411c81745 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -7217,6 +7217,11 @@ void Sema::checkInitializerLifetime(const InitializedEntity &Entity,
         if (pathContainsInit(Path))
           return false;
 
+        // Suppress false positives for code like the below:
+        //   Ctor(unique_ptr<T> up) : member(*up), member2(move(up)) {}
+        if (IsLocalGslOwner && pathOnlyInitializesGslPointer(Path))
+          return false;
+
         auto *DRE = dyn_cast<DeclRefExpr>(L);
         auto *VD = DRE ? dyn_cast<VarDecl>(DRE->getDecl()) : nullptr;
         if (!VD) {
diff --git a/test/Sema/warn-lifetime-analysis-nocfg.cpp b/test/Sema/warn-lifetime-analysis-nocfg.cpp
index efa54fe662..c558901cf2 100644
--- a/test/Sema/warn-lifetime-analysis-nocfg.cpp
+++ b/test/Sema/warn-lifetime-analysis-nocfg.cpp
@@ -120,6 +120,13 @@ void initLocalGslPtrWithTempOwner() {
 }
 
 namespace std {
+template<class T> struct remove_reference       { typedef T type; };
+template<class T> struct remove_reference<T &>  { typedef T type; };
+template<class T> struct remove_reference<T &&> { typedef T type; };
+
+template<class T>
+typename remove_reference<T>::type &&move(T &&t) noexcept;
+
 template <typename T>
 struct basic_iterator {
   basic_iterator operator++();
@@ -153,6 +160,7 @@ struct basic_string {
 
 template<typename T>
 struct unique_ptr {
+  T &operator*();
   T *get() const;
 };
 
@@ -217,3 +225,10 @@ int &doNotFollowReferencesForLocalOwner() {
 const char *trackThroughMultiplePointer() {
   return std::basic_string_view<char>(std::basic_string<char>()).begin(); // expected-warning {{returning address of local temporary object}}
 }
+
+struct X {
+  X(std::unique_ptr<int> up) : pointee(*up), pointer(std::move(up)) {}
+
+  int &pointee;
+  std::unique_ptr<int> pointer;
+};