Major Description
Seeing an UBSAN failure on Ubuntu 14.04 with clang 3.6.0:
$ ./build/latest/schema-test
[==========] Running 12 tests from 2 test cases.
[----------] Global test environment set-up.
[----------] 11 tests from TestSchema
[ RUN ] TestSchema.TestSchema
/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_iterator.h:739:16: runtime error: reference binding to null pointer of type 'const kudu::ColumnSchema'
SUMMARY: AddressSanitizer: undefined-behavior /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_iterator.h:739
mpercy@mpercy-ThinkPad-T530:~/src/kudu$ clang++ --version
clang version 3.6.0 (tags/RELEASE_360/final)
Target: x86_64-unknown-linux-gnu
Thread model: posix
$ /usr/bin/gdb --args ./build/latest/schema-test --gtest_break_on_failure
(gdb) b __ubsan::Diag::~Diag
Breakpoint 1 at 0x524bb1: file /home/development/llvm/3.6.0/final/llvm.src/projects/compiler-rt/lib/ubsan/ubsan_diag.cc, line 319.
(gdb) r
Starting program: /home/mpercy/src/kudu/build/fastdebug/schema-test --gtest_break_on_failure
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff2642880 (LWP 1120)]
[==========] Running 12 tests from 2 test cases.
[----------] Global test environment set-up.
[----------] 11 tests from TestSchema
[ RUN ] TestSchema.TestSchema
Breakpoint 1, ~Diag () at /home/development/llvm/3.6.0/final/llvm.src/projects/compiler-rt/lib/ubsan/ubsan_diag.cc:319
319 /home/development/llvm/3.6.0/final/llvm.src/projects/compiler-rt/lib/ubsan/ubsan_diag.cc: No such file or directory.
(gdb) bt
#0 ~Diag () at /home/development/llvm/3.6.0/final/llvm.src/projects/compiler-rt/lib/ubsan/ubsan_diag.cc:319
#1 0x0000000000525f71 in handleTypeMismatchImpl () at /home/development/llvm/3.6.0/final/llvm.src/projects/compiler-rt/lib/ubsan/ubsan_handlers.cc:64
#2 0x000000000052600d in __ubsan_handle_type_mismatch_abort () at /home/development/llvm/3.6.0/final/llvm.src/projects/compiler-rt/lib/ubsan/ubsan_handlers.cc:75
#3 0x00007ffff7b7b7cc in __gnu_cxx::__normal_iterator<kudu::ColumnSchema const*, std::vector<kudu::ColumnSchema, std::allocator<kudu::ColumnSchema> > >::operator* (this=<optimized out>)
at /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_iterator.h:739
#4 0x00007ffff7b7b6fe in std::vector<kudu::ColumnSchema, std::allocator<kudu::ColumnSchema> >::front (this=<optimized out>) at /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_vector.h:848
#5 0x00007ffff7b757a2 in std::vector<kudu::ColumnSchema, std::allocator<kudu::ColumnSchema> >::data (this=0x7fffffffcc00) at /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_vector.h:887
#6 0x00007ffff7b6f3c3 in kudu::Schema::memory_footprint_excluding_this (this=0x7fffffffcc00) at src/kudu/common/schema.cc:337
#7 0x000000000052a33d in kudu::tablet::TestSchema_TestSchema_Test::TestBody (this=<optimized out>) at src/kudu/common/schema-test.cc:48
#8 0x00007ffff6283219 in HandleSehExceptionsInMethodIfSupported<testing::Test, void> (location=0x7ffff6298d4c "the test body", method=<optimized out>, object=<optimized out>) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:2078
#9 testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void> (object=object@entry=0x60200000a690, method=<optimized out>, location=location@entry=0x7ffff6298d4c "the test body")
at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:2114
#10 0x00007ffff6274cff in testing::Test::Run (this=this@entry=0x60200000a690) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:2151
#11 0x00007ffff6274dbd in testing::TestInfo::Run (this=0x60f00000ee60) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:2326
#12 0x00007ffff6274ed5 in testing::TestCase::Run (this=0x6110000098c0) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:2444
#13 0x00007ffff6275188 in testing::internal::UnitTestImpl::RunAllTests (this=0x61500000fa80) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:4315
#14 0x00007ffff6275429 in HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool> (location=<optimized out>, method=<optimized out>, object=<optimized out>) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:2078
#15 HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool> (location=0x7ffff629a650 "auxiliary test code (environments or event listeners)",
method=(bool (testing::internal::UnitTestImpl::*)(testing::internal::UnitTestImpl * const)) 0x7ffff6274f40 <testing::internal::UnitTestImpl::RunAllTests()>, object=0x61500000fa80) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:2114
#16 testing::UnitTest::Run (this=<optimized out>) at /home/mpercy/src/kudu/thirdparty/gmock-1.7.0/gtest/src/gtest.cc:3929
#17 0x00007ffff7fef508 in main (argc=<optimized out>, argv=<optimized out>) at src/kudu/util/test_main.cc:37
#18 0x00007ffff5051ec5 in __libc_start_main (main=0x47c560 <main@plt>, argc=2, argv=0x7fffffffdb18, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffdb08) at libc-start.c:287
#19 0x000000000047d5be in _start ()
(gdb) f 5
#5 0x00007ffff7b757a2 in std::vector<kudu::ColumnSchema, std::allocator<kudu::ColumnSchema> >::data (this=0x7fffffffcc00) at /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_vector.h:887
887 { return std::__addressof(front()); }
(gdb) list
883 #else
884 const_pointer
885 #endif
886 data() const _GLIBCXX_NOEXCEPT
887 { return std::__addressof(front()); }
(gdb) f 4
#4 0x00007ffff7b7b6fe in std::vector<kudu::ColumnSchema, std::allocator<kudu::ColumnSchema> >::front (this=<optimized out>) at /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_vector.h:848
848 { return *begin(); }
(gdb) list
846 const_reference
847 front() const
848 { return *begin(); }
(gdb) f 3
#3 0x00007ffff7b7b7cc in __gnu_cxx::__normal_iterator<kudu::ColumnSchema const*, std::vector<kudu::ColumnSchema, std::allocator<kudu::ColumnSchema> > >::operator* (this=<optimized out>)
at /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_iterator.h:739
(gdb) list
736 // Forward iterator requirements
737 reference
738 operator*() const
739 { return *_M_current; }
(gdb) p _M_current
$1 = (const kudu::ColumnSchema *) 0x0