[Bug go/61620] New: FAIL: go.test/test/fixedbugs/bug242.go execution, -O2 -g

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61620

            Bug ID: 61620
           Summary: FAIL: go.test/test/fixedbugs/bug242.go execution,  -O2
                    -g
           Product: gcc
           Version: 4.10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: go
          Assignee: ian at airs dot com
          Reporter: ubizjak at gmail dot com
                CC: cmang at google dot com

Execute of go.test/test/fixedbugs/bug242.go fails on i686-linux-gnu with "fatal
error: freeing too small block".

[uros@localhost test]$ LD_LIBRARY_PATH=. gdb ./bug242.x             
GNU gdb (GDB) Fedora 7.7.1-13.fc20
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Reading symbols from ./bug242.x...done.
(gdb) r
Starting program: /home/uros/test/bug242.x 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 0xf756acc0 (LWP 5016)]
fatal error: freeing too small block

goroutine 16 [running]:
runtime_dopanic
        /home/uros/gcc-svn/trunk/libgo/runtime/panic.c:129
runtime_throw
        /home/uros/gcc-svn/trunk/libgo/runtime/panic.c:167
__go_free
        /home/uros/gcc-svn/trunk/libgo/runtime/malloc.goc:366
__go_map_delete
        /home/uros/gcc-svn/trunk/libgo/runtime/go-map-delete.c:50
runtime.mapdelete
        /home/uros/gcc-svn/trunk/libgo/runtime/map.goc:47
main.main
       
/home/uros/gcc-svn/trunk/gcc/testsuite/go.test/test/fixedbugs/bug242.go:96
runtime_main
        /home/uros/gcc-svn/trunk/libgo/runtime/proc.c:571
panic during panic

goroutine 16 [running]:
runtime_dopanic
        /home/uros/gcc-svn/trunk/libgo/runtime/panic.c:129
runtime_startpanic
        /home/uros/gcc-svn/trunk/libgo/runtime/panic.c:98
runtime_throw
        /home/uros/gcc-svn/trunk/libgo/runtime/panic.c:165
runtime_mallocgc
        /home/uros/gcc-svn/trunk/libgo/runtime/malloc.goc:115
__go_alloc
        /home/uros/gcc-svn/trunk/libgo/runtime/malloc.goc:333
callback
        /home/uros/gcc-svn/trunk/libgo/runtime/go-caller.c:47
dwarf_lookup_pc
        /home/uros/gcc-svn/trunk/libbacktrace/dwarf.c:2838
dwarf_fileline
        /home/uros/gcc-svn/trunk/libbacktrace/dwarf.c:2877
backtrace_pcinfo
        /home/uros/gcc-svn/trunk/libbacktrace/fileline.c:176
__go_file_line
        /home/uros/gcc-svn/trunk/libgo/runtime/go-caller.c:125
runtime_printcreatedby
        /home/uros/gcc-svn/trunk/libgo/runtime/proc.c:636
runtime_dopanic
        /home/uros/gcc-svn/trunk/libgo/runtime/panic.c:130
runtime_throw
        /home/uros/gcc-svn/trunk/libgo/runtime/panic.c:167
__go_free
        /home/uros/gcc-svn/trunk/libgo/runtime/malloc.goc:366
__go_map_delete
        /home/uros/gcc-svn/trunk/libgo/runtime/go-map-delete.c:50
runtime.mapdelete
        /home/uros/gcc-svn/trunk/libgo/runtime/map.goc:47
main.main
       
/home/uros/gcc-svn/trunk/gcc/testsuite/go.test/test/fixedbugs/bug242.go:96
runtime_main
        /home/uros/gcc-svn/trunk/libgo/runtime/proc.c:571
stack trace unavailable
[Thread 0xf756acc0 (LWP 5016) exited]
[Inferior 1 (process 5012) exited with code 04]


Breakpoint in runtime_dopanic:

Breakpoint 1, runtime_dopanic (unused=0) at
/home/uros/gcc-svn/trunk/libgo/runtime/panic.c:114
114     {
(gdb) bt
#0  runtime_dopanic (unused=0) at
/home/uros/gcc-svn/trunk/libgo/runtime/panic.c:114
#1  0xf7978ddf in runtime_throw (s=0xf7c90526 "freeing too small block") at
/home/uros/gcc-svn/trunk/libgo/runtime/panic.c:167
#2  0xf7981f7d in __go_free (v=0x18204018) at
/home/uros/gcc-svn/trunk/libgo/runtime/malloc.goc:366
#3  0xf796a8a4 in __go_map_delete (map=0x18200000, key=0xf6f1cf39) at
/home/uros/gcc-svn/trunk/libgo/runtime/go-map-delete.c:50
#4  0xf7982d35 in runtime.mapdelete (h=0x18200000, key=0xf6f1cf39 "\r") at
/home/uros/gcc-svn/trunk/libgo/runtime/map.goc:47
#5  0x08049eb6 in main.main () at
/home/uros/gcc-svn/trunk/gcc/testsuite/go.test/test/fixedbugs/bug242.go:96
(gdb) f 2
#2  0xf7981f7d in __go_free (v=0x18204018) at
/home/uros/gcc-svn/trunk/libgo/runtime/malloc.goc:366
366                     runtime_throw("freeing too small block");
(gdb) list
361             size = s->elemsize;
362             sizeclass = s->sizeclass;
363             // Objects that are smaller than TinySize can be allocated
using tiny alloc,
364             // if then such object is combined with an object with
finalizer, we will crash.
365             if(size < TinySize)
366                     runtime_throw("freeing too small block");
367
368             if(raceenabled)
369                     runtime_racefree(v);
370
(gdb) p size
$1 = 8
(gdb) p TinySize
$2 = TinySize
(gdb)