Auto-sync with upstream branch master
    
    Upstream commit: 860b0240a5645edd6490161de3f8d1d1f2786025
    
    - CVE-2018-1000001: Make getcwd fail if it cannot obtain an absolute path
      (#1533837)
    - elf: Synchronize DF_1_* flags with binutils (#1439328)
    - aarch64: fix static pie enabled libc when main is in a shared library
    - malloc: Ensure that the consolidated fast chunk has a sane size