[GHC] #15508: concprog001 fails with various errors

[GHC]

#15508: concprog001 fails with various errors
-------------------------------------+-------------------------------------
        Reporter:  osa1              |                Owner:  osa1
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Runtime crash     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #15571            |  Differential Rev(s):  Phab:D5051
       Wiki Page:                    |  (reverted), Phab:D5165, Phab:D5178
-------------------------------------+-------------------------------------

Comment (by osa1):

 Looking at the assembly again, this line

 {{{
    0x000000000051c5cc <+4>:     cmp    0x358(%r13),%r12
 }}}

 does heap limit check for allocation (`%r12` is the reg table, 0x358 =
 856,
 offset for `rHpLim`), then this line

 {{{
    0x000000000051c5d5 <+13>:    mov    0x360(%r13),%rax
 }}}

 Moves `rCCCS` (current cost centre stack) to `%rax`, so this line

 {{{
    0x000000000051c5dc <+20>:    addq   $0x3,0x48(%rax)
 }}}

 Tries to increment current cost centre stack's `mem_alloc`! Somehow
 `rCCCS->mem_alloc` is actually info pointer of another closure!

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15508#comment:27>
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