diff options
-rw-r--r-- | llvm/lib/VMCore/Type.cpp | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/llvm/lib/VMCore/Type.cpp b/llvm/lib/VMCore/Type.cpp index b815eec665b..0add0af3b84 100644 --- a/llvm/lib/VMCore/Type.cpp +++ b/llvm/lib/VMCore/Type.cpp @@ -453,8 +453,27 @@ void DerivedType::dropAllTypeUses() { if (NumContainedTys != 0) { // The type must stay abstract. To do this, we insert a pointer to a type // that will never get resolved, thus will always be abstract. - static Type *AlwaysOpaqueTy = OpaqueType::get(); - static PATypeHolder Holder(AlwaysOpaqueTy); + static Type *AlwaysOpaqueTy = 0; + static PATypeHolder* Holder = 0; + if (!AlwaysOpaqueTy) { + if (llvm_is_multithreaded()) { + llvm_acquire_global_lock(); + + if (!AlwaysOpaqueTy) { + Type *tmp = OpaqueType::get(); + PATypeHolder* tmp2 = new PATypeHolder(AlwaysOpaqueTy); + sys::MemoryFence(); + AlwaysOpaqueTy = tmp; + Holder = tmp2; + } + + llvm_release_global_lock(); + } else { + AlwaysOpaqueTy = OpaqueType::get(); + Holder = new PATypeHolder(AlwaysOpaqueTy); + } + } + ContainedTys[0] = AlwaysOpaqueTy; // Change the rest of the types to be Int32Ty's. It doesn't matter what we |