[all-commits] [llvm/llvm-project] 1876e6: [builtins][test] Avoid unportable mmap call in cle...

[llvm-git-migration via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 1876e6c83c7a713de2851af686417892cd717adc
      https://github.com/llvm/llvm-project/commit/1876e6c83c7a713de2851af686417892cd717adc
  Author: Rainer Orth <ro at gcc.gnu.org>
  Date:   2019-10-22 (Tue, 22 Oct 2019)

  Changed paths:
    M compiler-rt/test/builtins/Unit/clear_cache_test.c

  Log Message:
  -----------
  [builtins][test] Avoid unportable mmap call in clear_cache_test.c

Within the last two weeks, the Builtins-*-sunos :: clear_cache_test.c started to FAIL
on Solaris.  Running it under truss shows

  mmap(0x00000000, 128, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANON, 0, 0) Err#22 EINVAL
  _exit(1)

While there are several possible reasons mmap can return EINVAL on Solaris, it turns
out it's this one (from mmap(2)):

  MAP_ANON  was  specified,  but the file descriptor was not
   -1.

And indeed even the Linux mmap(2) documents this as unportable:

  MAP_ANONYMOUS
          The mapping is not backed by any file; its contents are initial‐
          ized to zero.  The fd argument is ignored; however, some  imple‐
          mentations require fd to be -1 if MAP_ANONYMOUS (or MAP_ANON) is
          specified, and portable applications should  ensure  this.   The

This patch follows this advise.  Tested on x86_64-pc-linux-gnu, amd64-pc-solaris2.11
and sparcv9-sun-solaris2.11.

Differential Revision: https://reviews.llvm.org/D68455

llvm-svn: 375490