[libcxx-commits] [PATCH] D140453: [libc++] Remove HIDE_FROM_ABI from virtual functions

[Louis Dionne via Phabricator via libcxx-commits]

ldionne created this revision.
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_LIBCPP_HIDE_FROM_ABI (which is what _LIBCPP_INLINE_VISIBILITY is) uses
ABI tags to avoid ODR violations when linking together object files
compiled against different versions of libc++. However, pointer
authentication uses the mangled name of the function to sign the
function pointer in the vtable, which means that the ABI tag effectively
changes how the pointers are signed.

This leads to PAC failures when passing an object that holds one of these
pointers in its vtable across an ABI boundary: one side will sign the
pointer using one function mangling (with one ABI tag), and the other
side will authenticate the pointer expecting it to have a different
signature, which won't work.

This patch is the result of a manual inspection of the code. However, we
should also setup a clang-tidy check to find those out in the future.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D140453

Files:
  libcxx/include/__functional/function.h
  libcxx/include/future
  libcxx/include/locale
  libcxx/include/regex


Index: libcxx/include/regex
===================================================================
--- libcxx/include/regex
+++ libcxx/include/regex
@@ -1446,12 +1446,9 @@
 
     _LIBCPP_INLINE_VISIBILITY
     __node() {}
-    _LIBCPP_INLINE_VISIBILITY
     virtual ~__node() {}
 
-    _LIBCPP_INLINE_VISIBILITY
     virtual void __exec(__state&) const {}
-    _LIBCPP_INLINE_VISIBILITY
     virtual void __exec_split(bool, __state&) const {}
 };
 
Index: libcxx/include/locale
===================================================================
--- libcxx/include/locale
+++ libcxx/include/locale
@@ -2479,7 +2479,7 @@
     static locale::id id;
 
 protected:
-    _LIBCPP_HIDE_FROM_ABI ~time_put() override {}
+    ~time_put() override {}
     virtual iter_type do_put(iter_type __s, ios_base&, char_type, const tm* __tm,
                              char __fmt, char __mod) const;
 
Index: libcxx/include/future
===================================================================
--- libcxx/include/future
+++ libcxx/include/future
@@ -1626,7 +1626,6 @@
 public:
     _LIBCPP_INLINE_VISIBILITY
     __packaged_task_base() {}
-    _LIBCPP_INLINE_VISIBILITY
     virtual ~__packaged_task_base() {}
     virtual void __move_to(__packaged_task_base*) _NOEXCEPT = 0;
     virtual void destroy() = 0;
Index: libcxx/include/__functional/function.h
===================================================================
--- libcxx/include/__functional/function.h
+++ libcxx/include/__functional/function.h
@@ -262,7 +262,7 @@
     __base& operator=(const __base&);
 public:
     _LIBCPP_INLINE_VISIBILITY __base() {}
-    _LIBCPP_INLINE_VISIBILITY virtual ~__base() {}
+    virtual ~__base() {}
     virtual __base* __clone() const = 0;
     virtual void __clone(__base*) const = 0;
     virtual void destroy() _NOEXCEPT = 0;


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