[llvm-dev] [msan] Failing mmap.cc test

[David Greene via llvm-dev]

The mmap.cc test is failing for me on aarch64 SuSE 12.  The assert
assert(AddrIsApp(p)) fails.  The last value printed from mmap is
0xf00000000 which is indeed not MAP_FAILED but also not a valid address
acoording to mmap.cc's mapping table.

Is there something about SuSE 12's kernel that behaves differently from
what this test expects?  I am not a kernel guy...

The sequence of the last handful of addresses returned and printed by
the test is:

0x5600000000
0x5500000000
0x5400000000
0x5300000000
0x5200000000
0x5100000000
0x5000000000
0xf00000000

That jump in value looks suspicious to me.

Also, a lot of sanitizer symbols are reported to be "optimized out" by
gdb even with a debug LLVM build and gdb gets very confused about where
execution is going.  Is that expected?  Is there a special cmake build
flag to enable more debug info in compiler-rt and/or the sanitizer
runtime?

                             -David