RFR: 8214976: Warn about uses of functions replaced for portability

[Harold Seigel]

Please review this new attempt to resolve JDK-8214976.  This fix adds Pragmas to generate compilation errors, when using gcc, if calling a native system function instead of the os:: version of the function.  The fix includes changes to calls in non-shared code because it is cleaner than adding PRAGMAs and, for some cases, the os:: version of a function has added value, such as asserts and RESTARTABLE.  This fix slightly changes the signature of os::abort() so it wouldn't conflict with native abort() functions.  Changes to Windows code is left for a future RFE.

This fix was tested with Mach5 tiers 1-2 on Linux, Mac OS, and Windows, Mach5 tiers 3-5 on Linux x64, and Mach5 builds of Zero, PPC, and s390.

Thanks, Harold

-------------

Commit messages:
 - 8214976: Warn about uses of functions replaced for portability

Changes: https://git.openjdk.java.net/jdk/pull/7248/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7248&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8214976
  Stats: 148 lines in 15 files changed: 105 ins; 0 del; 43 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7248.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7248/head:pull/7248

PR: https://git.openjdk.java.net/jdk/pull/7248