[GHC] #10518: unregisterised GHC generates incorrect 0xUL literals for certain onstants

13 Jun 2015


      #10518: unregisterised GHC generates incorrect 0xUL literals for certain onstants
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              Reporter:  slyfox      |             Owner:  slyfox
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.10.1
              Keywords:              |  Operating System:  Unknown/Multiple
          Architecture:              |   Type of failure:  None/Unknown
  Unknown/Multiple                   |        Blocked By:
             Test Case:              |   Related Tickets:
              Blocking:              |
Differential Revisions:              |
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 jakzale reports:
 21:47:27 < int-e> Oh, nice. Yes, indeed pprHexVal (2^32) W32 (function
 from cmm/PprC.hs) would result in 0xU.
 21:50:29 < jakzale> int-e: yes, truncInt takes module 2^32, then go
 returns empty string (I guess)

 Here comes the test:
 {{{
 $ cat a.cmm

 foo() {
     bits64 a;
     a = 0x10000000000000000; // overflows 64 bits
     return (a);
 }

 $ inplace/bin/ghc-stage2 -c a.cmm
 /tmp/ghc8580_0/ghc_2.hc: In function 'foo':

 /tmp/ghc8580_0/ghc_2.hc:8:7: error:
      error: invalid suffix "xUL" on integer constant
      _c0 = 0xUL;
            ^
 }}}
 I've broke it with commit:43f1b2ecd1960fa7377cf55a2b97c66059a701ef
 when introduced truncation that can generate more zeroes.

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Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10518
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