ghci: internal error: ASSERTION FAILED: file rts/Interpreter.c, line 773

It's a ghc-HEAD on amd64 ./configure --enable-unregisterised.

One of faulty tests is a:

ghc-unreg/testsuite/tests/ghci/should_run $ '/home/slyfox/dev/git/ghc-unreg/inplace/bin/ghc-stage2' -fforce-recomp -dcore-lint -dcmm-lint -dno-debug-output -no-user-package-db -rtsopts -optc-fno-builtin -fno-warn-tabs -fno-ghci-history ghcirun002.hs --interactive -v0 -ignore-dot-ghci +RTS -I0.1 -RTS

*Main> main

(<interactive>: internal error: ASSERTION FAILED: file rts/Interpreter.c, line 773

    (GHC version 7.9.20141020 for x86_64_unknown_linux)
    Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
Aborted

The assertion failure is triggered by stack overflow check when handling ... stack overflow!

    // Stack check
    if (Sp - INTERP_STACK_CHECK_THRESH < SpLim) {
        Sp -= 2;
        Sp[1] = (W_)obj;
        Sp[0] = (W_)&stg_apply_interp_info; // placeholder, really
/* 773 */ RETURN_TO_SCHEDULER(ThreadInterpret, StackOverflow);
    }

/* ... RETURN_TO_SCHEDULER decl: */
#define RETURN_TO_SCHEDULER(todo,retcode)       \
/* this triggers assert */   SAVE_STACK_POINTERS; \
   cap->r.rCurrentTSO->what_next = (todo);      \
   threadPaused(cap,cap->r.rCurrentTSO);                \
   cap->r.rRet = (retcode);                     \
   return cap;

/* ... SAVE_STACK_POINTERS decl: */
#define SAVE_STACK_POINTERS                     \
    ASSERT(Sp > SpLim); \
    cap->r.rCurrentTSO->stackobj->sp = Sp

In our case Sp == SpLim. That means we have written one word out-of-stack-bounds, right?

Trac metadata

Trac field	Value
Version	7.9
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	GHCi
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	hvr, simonmar
Operating system
Architecture