Created attachment 119507 [details]
Full output of valgrind -v

SUMMARY
 Trying to memcheck my executable compiled under mpicxx gives the following error: 

==68279== valgrind: Unrecognised instruction at address 0x100764b7b.
==68279==    at 0x100764B7B: _dispatch_kq_poll (in /usr/lib/system/libdispatch.dylib)

My code runs fine outside valgrind, it is stable, and there are no warnings about bad jumps before the error in valgrind. The instruction seems to be in a system library, so I think the instruction is legitimate.

OBSERVED RESULT

Full output of valgrind -v is attached. 

EXPECTED RESULT


SOFTWARE/OS VERSIONS

Valgrind 3.15.0 downloaded and built today, tested with 'valgrind ls -L'.

mpicxx --version:
Apple LLVM version 10.0.0 (clang-1000.11.45.5)
Target: x86_64-apple-darwin17.7.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

My executable compiled with:
mpicxx -std=c++11 -g -O3 ...  -lstdc++

uname -a:
Darwin Biocomplexitys-Eubank.local 17.7.0 Darwin Kernel Version 17.7.0: Thu Dec 20 21:47:19 PST 2018; root:xnu-4570.71.22~1/RELEASE_X86_64 x86_64