commit 03544830138f4643c49f048a771f09478902d93b
author George Karpenkov <ekarpenkov@apple.com> Fri Nov 03 00:36:03 2017 +0000
committer George Karpenkov <ekarpenkov@apple.com> Fri Nov 03 00:36:03 2017 +0000
tree 3fd04a2e3b78542d4300653b4f711cc94d13865d
parent 7cdb10f1aabfe57b3e1dcb1a8e5a064b1c7343dc

[analyzer] do not crash on libcxx03 call_once implementation

Addresses https://bugs.llvm.org/show_bug.cgi?id=35075, rdar://35230961

Differential Revision: https://reviews.llvm.org/D39518

llvm-svn: 317293

clang/lib/Analysis/BodyFarm.cpp

diff --git a/clang/lib/Analysis/BodyFarm.cpp b/clang/lib/Analysis/BodyFarm.cpp
index 58a129c..3e62ae5 100644
--- a/clang/lib/Analysis/BodyFarm.cpp
+++ b/clang/lib/Analysis/BodyFarm.cpp
@@ -325,6 +325,16 @@
 
   const ParmVarDecl *Flag = D->getParamDecl(0);
   const ParmVarDecl *Callback = D->getParamDecl(1);
+
+  if (!Callback->getType()->isReferenceType()) {
+    llvm::dbgs() << "libcxx03 std::call_once implementation, skipping.\n";
+    return nullptr;
+  }
+  if (!Flag->getType()->isReferenceType()) {
+    llvm::dbgs() << "unknown std::call_once implementation, skipping.\n";
+    return nullptr;
+  }
+
   QualType CallbackType = Callback->getType().getNonReferenceType();
 
   // Nullable pointer, non-null iff function is a CXXRecordDecl.
@@ -346,15 +356,13 @@
   // Otherwise, try libstdc++ implementation, with a field
   // `_M_once`
   if (!FlagFieldDecl) {
-    DEBUG(llvm::dbgs() << "No field __state_ found on std::once_flag struct, "
-                       << "assuming libstdc++ implementation\n");
     FlagFieldDecl = M.findMemberField(FlagRecordDecl, "_M_once");
   }
 
   if (!FlagFieldDecl) {
-    DEBUG(llvm::dbgs() << "No field _M_once found on std::once flag struct: "
-                       << "unknown std::call_once implementation, "
-                       << "ignoring the call");
+    DEBUG(llvm::dbgs() << "No field _M_once or __state_ found on "
+                       << "std::once_flag struct: unknown std::call_once "
+                       << "implementation, ignoring the call.");
     return nullptr;
   }
 
@@ -388,9 +396,9 @@
 
   // First two arguments are used for the flag and for the callback.
   if (D->getNumParams() != CallbackFunctionType->getNumParams() + 2) {
-    DEBUG(llvm::dbgs() << "Number of params of the callback does not match "
-                       << "the number of params passed to std::call_once, "
-                       << "ignoring the call");
+    DEBUG(llvm::dbgs() << "Types of params of the callback do not match "
+                       << "params passed to std::call_once, "
+                       << "ignoring the call\n");
     return nullptr;
   }