From 72a3108e1e204fd63ba486ef59eccd44219a7a56 Mon Sep 17 00:00:00 2001
From: Noemi Erli <nerli@mozilla.com>
Date: Tue, 1 Aug 2023 15:09:51 +0300
Subject: [PATCH] Backed out changeset a2017655dd34 (bug 1844484) for causing
 failures in test_crash_purevirtual.js

---
 build/pure_virtual/moz.build                  | 17 ------------
 build/pure_virtual/pure_virtual.c             | 27 -------------------
 mfbt/moz.build                                |  5 ----
 python/mozbuild/mozbuild/frontend/emitter.py  |  2 --
 .../test/unit/test_crash_purevirtual.js       |  8 ++++++
 5 files changed, 8 insertions(+), 51 deletions(-)
 delete mode 100644 build/pure_virtual/moz.build
 delete mode 100644 build/pure_virtual/pure_virtual.c

diff --git a/build/pure_virtual/moz.build b/build/pure_virtual/moz.build
deleted file mode 100644
index c49cb8fe80cb..000000000000
--- a/build/pure_virtual/moz.build
+++ /dev/null
@@ -1,17 +0,0 @@
-# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
-# vim: set filetype=python:
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-Library("pure_virtual")
-
-SOURCES += ["pure_virtual.c"]
-
-FORCE_STATIC_LIB = True
-
-USE_STATIC_LIBS = True
-
-# Build a real library so that the linker can remove it if the symbol
-# is never used.
-NO_EXPAND_LIBS = True
diff --git a/build/pure_virtual/pure_virtual.c b/build/pure_virtual/pure_virtual.c
deleted file mode 100644
index 23b18f2aae7d..000000000000
--- a/build/pure_virtual/pure_virtual.c
+++ /dev/null
@@ -1,27 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#include <mozilla/Assertions.h>
-
-// This function is used in vtables to point at pure virtual methods.
-// The implementation in the standard library usually aborts, but
-// the function is normally never called (a call would be a bug).
-// Each of these entries in vtables, however, require an unnecessary
-// dynamic relocation. Defining our own function makes the linker
-// point the vtables here instead of the standard library, replacing
-// the dynamic relocations with relative relocations.
-//
-// On Windows, it doesn't really make a difference, but on macOS it
-// can be packed better, saving about 10KB in libxul, and on 64-bits
-// ELF systems, with packed relative relocations, it saves 140KB.
-//
-// Another advantage of having our own is that we can use MOZ_CRASH
-// instead of the system's abort.
-#ifdef _MSC_VER
-int __cdecl _purecall() { MOZ_CRASH("pure virtual call"); }
-#else
-__attribute__((visibility("hidden"))) void __cxa_pure_virtual() {
-  MOZ_CRASH("pure virtual call");
-}
-#endif
diff --git a/mfbt/moz.build b/mfbt/moz.build
index 5f8c0925a545..4cdcfcd0fc3d 100644
--- a/mfbt/moz.build
+++ b/mfbt/moz.build
@@ -205,8 +205,3 @@ if CONFIG["MOZ_NEEDS_LIBATOMIC"]:
     OS_LIBS += ["atomic"]
 
 DEFINES["LZ4LIB_VISIBILITY"] = ""
-
-# This is kind of gross because this is not a subdirectory,
-# but pure_virtual requires mfbt to build and some projects
-# don't use mfbt.
-DIRS += ["../build/pure_virtual"]
diff --git a/python/mozbuild/mozbuild/frontend/emitter.py b/python/mozbuild/mozbuild/frontend/emitter.py
index f4100772418e..360205f8ec97 100644
--- a/python/mozbuild/mozbuild/frontend/emitter.py
+++ b/python/mozbuild/mozbuild/frontend/emitter.py
@@ -388,8 +388,6 @@ class TreeMetadataEmitter(LoggingMixin):
                     context, obj, variable, self.STDCXXCOMPAT_NAME[obj.KIND]
                 )
             if obj.KIND == "target":
-                if "pure_virtual" in self._libs:
-                    self._link_library(context, obj, variable, "pure_virtual")
                 for lib in context.config.substs.get("STLPORT_LIBS", []):
                     obj.link_system_library(lib)
 
diff --git a/toolkit/crashreporter/test/unit/test_crash_purevirtual.js b/toolkit/crashreporter/test/unit/test_crash_purevirtual.js
index cc81c008df09..e482eaa41586 100644
--- a/toolkit/crashreporter/test/unit/test_crash_purevirtual.js
+++ b/toolkit/crashreporter/test/unit/test_crash_purevirtual.js
@@ -6,6 +6,14 @@ add_task(async function run_test() {
     return;
   }
 
+  var isOSX = "nsILocalFileMac" in Ci;
+  if (isOSX) {
+    dump(
+      "INFO | test_crash_purevirtual.js | TODO: purecalls not caught on OS X\n"
+    );
+    return;
+  }
+
   // Try crashing with a pure virtual call
   await do_crash(
     function () {