[tbb-bugs] #17508 [Tor Browser]: Using FORTIFY_SOURCE breaks inlining of memcpy when comiling Tor Browser with ASan

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#17508: Using FORTIFY_SOURCE breaks inlining of memcpy when comiling Tor Browser
with ASan
-----------------------------+---------------------------
     Reporter:  gk           |      Owner:  tbb-team
         Type:  defect       |     Status:  new
     Priority:  Medium       |  Milestone:
    Component:  Tor Browser  |    Version:
     Severity:  Normal       |   Keywords:  tbb-hardening
Actual Points:               |  Parent ID:
       Points:               |    Sponsor:
-----------------------------+---------------------------
 While it is a known thing that ASan is not working particularly well with
 `FORTIFY_SOURCE` (#14821 and https://code.google.com/p/address-
 sanitizer/issues/detail?id=247) this combination is breaking Tor Browser
 compilation directly:
 {{{
 In file included from ../../dist/system_wrappers/sys/cdefs.h:3:0,
                  from /usr/include/features.h:346,
                  from ../../dist/system_wrappers/features.h:3,
                  from /home/ubuntu/install/gcc/include/c++/5.1.0/x86_64
 -unknown-linux-gnu/bits/os_defines.h:39,
                  from /home/ubuntu/install/gcc/include/c++/5.1.0/x86_64
 -unknown-linux-gnu/bits/c++config.h:482,
                  from
 /home/ubuntu/install/gcc/include/c++/5.1.0/cstddef:44,
                  from ../../dist/system_wrappers/cstddef:3,
                  from ../../dist/include/mozilla/Compiler.h:46,
                  from ../../dist/include/mozilla/Attributes.h:12,
                  from ../../dist/include/mozilla/Assertions.h:16,
                  from ../../dist/include/mozilla/ArrayUtils.h:14,
                  from /home/ubuntu/build/tor-
 browser/xpcom/threads/BackgroundHangMonitor.cpp:7,
                  from /home/ubuntu/build/tor-browser/obj-x86_64-unknown-
 linux-gnu/xpcom/threads/Unified_cpp_xpcom_threads0.cpp:2:
 /usr/include/bits/string3.h: In member function 'void
 mozilla::ThreadStackHelper::FillThreadContext(void*)':
 /usr/include/bits/string3.h:49:1: error: inlining failed in call to
 always_inline 'void* memcpy(void*, const void*, size_t) throw ()':
 function attribute mismatch
  __NTH (memcpy (void *__restrict __dest, __const void *__restrict __src,
  ^
 In file included from /home/ubuntu/build/tor-browser/obj-x86_64-unknown-
 linux-gnu/xpcom/threads/Unified_cpp_xpcom_threads0.cpp:29:0:
 /home/ubuntu/build/tor-browser/xpcom/threads/ThreadStackHelper.cpp:730:66:
 error: called from here
           &context.uc_mcontext.gregs[REG_R8], 8 * sizeof(int64_t));
                                                                   ^
 make[5]: Leaving directory `/home/ubuntu/build/tor-browser/obj-x86_64
 -unknown-linux-gnu/xpcom/threads'
 make[5]: *** [Unified_cpp_xpcom_threads0.o] Error 1
 }}}
 It is not clear why this is happening right now. We only workaround this
 problem by backporting

 https://hg.mozilla.org/mozilla-central/rev/5e86358d4ec2
 https://hg.mozilla.org/mozilla-central/rev/33e89c9a4172

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17508>
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