[Mono-dev] Exceptions-x86.c r140989 causes exceptions.exe test to crash on Mac x86

[Tom Philpot]

While trying to rebuild the latest Mono SVN, I noticed that the
exceptions.exe was crashing during "make check". Digging a little deeper I
reverted the latest change to exceptions-x86.c (svn update -r PREV
mono/mono/mini/exceptions-x86.c) and everything passed.

The crash from the test case using r of exceptions-x86.c is as follows:

Test run: 
image=/Users/tom.philpot/External/mono-project/mono/mono/mini/exceptions.exe
, opts=
Stacktrace:

  at (wrapper managed-to-native)
object.__icall_wrapper___emul_fconv_to_ovf_u8 (double) <0x00004>
  at (wrapper managed-to-native)
object.__icall_wrapper___emul_fconv_to_ovf_u8 (double) <0xffffffff>
  at Tests.test_0_byte_cast () <0x00318>

Native stacktrace:

    0   mono                                0x0008e0da
mono_handle_native_sigsegv + 266
    1   mono                                0x00006eca
mono_sigsegv_signal_handler + 298
    2   libSystem.B.dylib                   0x949402bb _sigtramp + 43
    3   ???                                 0xffffffff 0x0 + 4294967295

Debug info from gdb:

warning: Trying to remove a section from the ordered section list that did
not exist at 0x29c000.
Attaching to process 53961.
Reading symbols for shared libraries . done
Reading symbols for shared libraries
............................................................................
........ done
0x948f7f95 in read$UNIX2003 ()
  4 process 53961 thread 0x2703  0x948d42c2 in semaphore_wait_trap ()
  3 process 53961 thread 0x2303  0x948db46e in __semwait_signal ()
  2 process 53961 thread 0x1103  0x948d4286 in mach_msg_trap ()
* 1 process 53961 thread 0x717  0x948f7f95 in read$UNIX2003 ()

Thread 4 (process 53961 thread 0x2703):
#0  0x948d42c2 in semaphore_wait_trap ()
#1  0x000f8013 in finalizer_thread (unused=0x0) at gc.c:1014
#2  0x001851ba in start_wrapper (data=0x60f4a0) at threads.c:657
#3  0x001b6225 in thread_start_routine (args=0x5dc434) at wthreads.c:286
#4  0x001d5483 in GC_start_routine (arg=0x593f60) at pthread_support.c:1390
#5  0x94905155 in _pthread_start ()
#6  0x94905012 in thread_start ()

Thread 3 (process 53961 thread 0x2303):
#0  0x948db46e in __semwait_signal ()
#1  0x948db2ef in nanosleep$UNIX2003 ()
#2  0x00199b10 in collection_thread (unused=0x0) at collection.c:34
#3  0x94905155 in _pthread_start ()
#4  0x94905012 in thread_start ()

Thread 2 (process 53961 thread 0x1103):
#0  0x948d4286 in mach_msg_trap ()
#1  0x948dba7c in mach_msg ()
#2  0x000c0dc4 in mach_exception_thread (arg=0x0) at mini-darwin.c:131
#3  0x001d5483 in GC_start_routine (arg=0x593f60) at pthread_support.c:1390
#4  0x94905155 in _pthread_start ()
#5  0x94905012 in thread_start ()

Thread 1 (process 53961 thread 0x717):
#0  0x948f7f95 in read$UNIX2003 ()
#1  0x0008e1cb in mono_handle_native_sigsegv (signal=11, ctx=0xbfffec38) at
mini-exceptions.c:1560
#2  0x00006eca in mono_sigsegv_signal_handler (_dummy=11, info=0xbfffebf8,
context=0xbfffec38) at mini.c:4583
#3  <signal handler called>
#4  0x0005a05e in mono_fconv_ovf_u8 (v=0) at jit-icalls.c:860
#5  0x016a23e7 in ?? ()
#6  0x016a1c49 in ?? ()
#7  0x00067d7d in mini_regression [inlined] () at driver.c:427
#8  0x00067d7d in mono_main (argc=16, argv=0xbffff0ec) at driver.c:484
#9  0x00001ff6 in start ()

=================================================================
Got a SIGSEGV while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
=================================================================