[analyzer] Fix missed leak from MSVC specific allocation functions

Add the wide character strdup variants (wcsdup, _wcsdup) and the MSVC
version of alloca (_alloca) and other differently named function used
by the Malloc checker.

A patch by Alexander Riccio!

Differential Revision: http://reviews.llvm.org/D17688

llvm-svn: 262894

1 files changed, 23 insertions, 13 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index fee030feb6d..f365e536676 100644
--- a/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -169,11 +169,12 @@ class MallocChecker : public Checker<check::DeadSymbols,
 {
 public:
   MallocChecker()
-      : II_alloca(nullptr), II_malloc(nullptr), II_free(nullptr),
-        II_realloc(nullptr), II_calloc(nullptr), II_valloc(nullptr),
-        II_reallocf(nullptr), II_strndup(nullptr), II_strdup(nullptr),
-        II_kmalloc(nullptr), II_if_nameindex(nullptr),
-        II_if_freenameindex(nullptr) {}
+      : II_alloca(nullptr), II_win_alloca(nullptr), II_malloc(nullptr),
+        II_free(nullptr), II_realloc(nullptr), II_calloc(nullptr),
+        II_valloc(nullptr), II_reallocf(nullptr), II_strndup(nullptr),
+        II_strdup(nullptr), II_win_strdup(nullptr), II_kmalloc(nullptr),
+        II_if_nameindex(nullptr), II_if_freenameindex(nullptr),
+        II_wcsdup(nullptr), II_win_wcsdup(nullptr) {}
 
   /// In pessimistic mode, the checker assumes that it does not know which
   /// functions might free the memory.
@@ -231,10 +232,11 @@ private:
   mutable std::unique_ptr<BugType> BT_MismatchedDealloc;
   mutable std::unique_ptr<BugType> BT_OffsetFree[CK_NumCheckKinds];
   mutable std::unique_ptr<BugType> BT_UseZerroAllocated[CK_NumCheckKinds];
-  mutable IdentifierInfo *II_alloca, *II_malloc, *II_free, *II_realloc,
-                         *II_calloc, *II_valloc, *II_reallocf, *II_strndup,
-                         *II_strdup, *II_kmalloc, *II_if_nameindex,
-                         *II_if_freenameindex;
+  mutable IdentifierInfo *II_alloca, *II_win_alloca, *II_malloc, *II_free,
+                         *II_realloc, *II_calloc, *II_valloc, *II_reallocf,
+                         *II_strndup, *II_strdup, *II_win_strdup, *II_kmalloc,
+                         *II_if_nameindex, *II_if_freenameindex, *II_wcsdup,
+                         *II_win_wcsdup;
   mutable Optional<uint64_t> KernelZeroFlagVal;
 
   void initIdentifierInfo(ASTContext &C) const;
@@ -540,9 +542,15 @@ void MallocChecker::initIdentifierInfo(ASTContext &Ctx) const {
   II_valloc = &Ctx.Idents.get("valloc");
   II_strdup = &Ctx.Idents.get("strdup");
   II_strndup = &Ctx.Idents.get("strndup");
+  II_wcsdup = &Ctx.Idents.get("wcsdup");
   II_kmalloc = &Ctx.Idents.get("kmalloc");
   II_if_nameindex = &Ctx.Idents.get("if_nameindex");
   II_if_freenameindex = &Ctx.Idents.get("if_freenameindex");
+
+  //MSVC uses `_`-prefixed instead, so we check for them too.
+  II_win_strdup = &Ctx.Idents.get("_strdup");
+  II_win_wcsdup = &Ctx.Idents.get("_wcsdup");
+  II_win_alloca = &Ctx.Idents.get("_alloca");
 }
 
 bool MallocChecker::isMemFunction(const FunctionDecl *FD, ASTContext &C) const {
@@ -585,7 +593,8 @@ bool MallocChecker::isCMemFunction(const FunctionDecl *FD,
     if (Family == AF_Malloc && CheckAlloc) {
       if (FunI == II_malloc || FunI == II_realloc || FunI == II_reallocf ||
           FunI == II_calloc || FunI == II_valloc || FunI == II_strdup ||
-          FunI == II_strndup || FunI == II_kmalloc)
+          FunI == II_win_strdup || FunI == II_strndup || FunI == II_wcsdup ||
+          FunI == II_win_wcsdup || FunI == II_kmalloc)
         return true;
     }
 
@@ -600,7 +609,7 @@ bool MallocChecker::isCMemFunction(const FunctionDecl *FD,
     }
 
     if (Family == AF_Alloca && CheckAlloc) {
-      if (FunI == II_alloca)
+      if (FunI == II_alloca || FunI == II_win_alloca)
         return true;
     }
   }
@@ -789,11 +798,12 @@ void MallocChecker::checkPostStmt(const CallExpr *CE, CheckerContext &C) const {
       State = ProcessZeroAllocation(C, CE, 1, State);
     } else if (FunI == II_free) {
       State = FreeMemAux(C, CE, State, 0, false, ReleasedAllocatedMemory);
-    } else if (FunI == II_strdup) {
+    } else if (FunI == II_strdup || FunI == II_win_strdup ||
+               FunI == II_wcsdup || FunI == II_win_wcsdup) {
       State = MallocUpdateRefState(C, CE, State);
     } else if (FunI == II_strndup) {
       State = MallocUpdateRefState(C, CE, State);
-    } else if (FunI == II_alloca) {
+    } else if (FunI == II_alloca || FunI == II_win_alloca) {
       State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State,
                            AF_Alloca);
       State = ProcessZeroAllocation(C, CE, 0, State);