[GHC] #14026: hs_init is not idempotent

24 Jul 2017


      #14026: hs_init is not idempotent
-------------------------------------+-------------------------------------
           Reporter:  Feuerbach      |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.0.2
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 hs_init tries to be idempotent by ignoring all calls but the first one.
 However, subsequent calls to hs_init do not set argc and argv correctly.

 Here's a test case:

 {{{
 #include "HsFFI.h"
 #include "stdio.h"

 void try_init() {
   char *argv[] = { "./test", "+RTS", "-s", "-RTS", "arg", 0 };
   char **argv_ptr = argv;
   int argc = sizeof(argv)/sizeof(argv[0]) - 1;
   hs_init(&argc, &argv_ptr);
   printf("%d\n", argc);
 }

 int main() {
   try_init();
   try_init();
 }
 }}}

 Result:

 {{{
 2
 5
 }}}

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14026
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