[Vm-dev] [OpenSmalltalk/opensmalltalk-vm] e8e9a5: compile linux64x64 newspeak.cog.spur with clang

[Nicolas Cellier]

  Branch: refs/heads/compile_newspeak_with_clang
  Home:   https://github.com/OpenSmalltalk/opensmalltalk-vm
  Commit: e8e9a534e1d9123b47c2fbab1c08d7864aab6e1c
      https://github.com/OpenSmalltalk/opensmalltalk-vm/commit/e8e9a534e1d9123b47c2fbab1c08d7864aab6e1c
  Author: Nicolas Cellier <nicolas.cellier.aka.nice at gmail.com>
  Date:   2019-10-24 (Thu, 24 Oct 2019)

  Changed paths:
    M build.linux64x64/newspeak.cog.spur/build.assert.itimerheartbeat/mvm
    M build.linux64x64/newspeak.cog.spur/build.assert/mvm
    M build.linux64x64/newspeak.cog.spur/build.debug.itimerheartbeat/mvm
    M build.linux64x64/newspeak.cog.spur/build.debug/mvm
    M build.linux64x64/newspeak.cog.spur/build.itimerheartbeat/mvm
    M build.linux64x64/newspeak.cog.spur/build/mvm

  Log Message:
  -----------
  compile linux64x64 newspeak.cog.spur with clang

Reason: there's been some problem showing recently with gcc stack handling
The newspeak boostrap failed with this error:

    +/home/travis/build/OpenSmalltalk/opensmalltalk-vm/products/nscogspur64linuxht/bin/nsvm -headless ns-2019-10-23.64.image NewspeakBootstrap.st
    Segmentation fault (core dumped)

Also remove the -fwrapv compilation flag.
It was once necessary, but we should not
The -fwrapv tells the compiler to assume that integer overflow will wrap instead of being undefined behavior.