Bug #11684: Pack#unpack test failure on Solaris 10 with Oracle Solaris Studio 12.4

• Status: Closed
• Assignee: ngoto (Naohisa Goto)
• Target version: -
• ruby -v: ruby 2.5.0dev (2017-12-19) [sparc64-solaris2.10]
• Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN

[ngoto (Naohisa Goto)]

On Solaris 10, when compiling ruby with Oracle Solaris Studio 12.4 with -xO4 optimization option, the following test failure is observed during make test-all. (tested with r52550)

  1) Failure:
TestPack#test_pack_unpack_atmark [XXXXX/test/ruby/test_pack.rb:548]:
<[nil]> expected but was
<[]>.

  2) Failure:
TestPack#test_short_string [/XXXXX/test/ruby/test_pack.rb:735]:
<[1, nil]> expected but was
<[1]>.

15885 tests, 2225854 assertions, 2 failures, 0 errors, 50 skips

It seems that String#unpack is incorrectly compiled with Oracle Solaris Studio 12.4 with -xO4.

$ irb
irb(main):001:0> [1,2].pack('i2')
=> "\x00\x00\x00\x01\x00\x00\x00\x02" ###<== OK
irb(main):002:0> "\x00\x00\x00\x01\x00\x00\x00\x02".unpack('i3')
=> [1, 2] ###<== [1, 2, nil] is expected

It seems that PACK_ITEM_ADJUST() is wiped out by wrong optimization.
I think this is a bug of Oracle Solaris Studio 12.4.

The failure is not observed with -xO3 or lower optimization option.
It is also not observed by using Oracle Solaris Studio 12.3, even speficying -xO4 optimization option.

[ngoto (Naohisa Goto)]

• Subject changed from Pack#unpack test failure on to Pack#unpack test failure on Solaris 10 with Oracle Solaris Studio 12.4

[ngoto (Naohisa Goto)]

• Status changed from Open to Closed

Applied in changeset r52559.

---

• pack.c (pack_unpack, AVOID_CC_BUG): Very ugly workaround for
  optimization bug of Oracle Solaris Studio 12.4 on Solaris
  with -xO4 optimization option. [Bug #11684]

[ngoto (Naohisa Goto)]

• Status changed from Closed to Open

The bug is also observed with Oracle Developer Studio 12.5 (the next version of Oracle Solaris Studio 12.4).

[ngoto (Naohisa Goto)]

• Status changed from Open to Closed

Applied in changeset trunk|r58358.

---

Workaround for optimization bug of Oracle Solaris Studio 12.4 and 12.5

• pack.c (pack_unpack, AVOID_CC_BUG): Very ugly workaround for
  optimization bug of Oracle Solaris Studio 12.4 and 12.5
  (Oracle Developer Studio 12.5) on Solaris with -xO4 optimization
  option. [Bug #11684] [ruby-core:80690]

[ngoto (Naohisa Goto)]

• Status changed from Closed to Open
• Assignee set to ngoto (Naohisa Goto)
• ruby -v changed from ruby 2.3.0dev (2015-11-12) [sparc64-solaris2.10] to ruby 2.5.0dev (2017-12-19) [sparc64-solaris2.10]

Reopen because this is also observed with Oracle Developer Studio 12.6.

[ngoto (Naohisa Goto)]

• Status changed from Open to Closed

Applied in changeset trunk|r61344.

---

Workaround for optimization bug of Oracle Developer Studio 12.4-12.6

• pack.c (pack_unpack, AVOID_CC_BUG): Very ugly workaround for
  optimization bug of Oracle Developer Studio (Oracle Solaris Studio)
  12.4, 12.5, and 12.6 on Solaris 10 with -xO4 optimization option.
  [Bug #11684] [ruby-core:84351]