Re: [gforth] FYI: gforth and gcc 4.7

[Andrew Haley]

On 04/12/2012 04:49 PM, Anton Ertl wrote:
> On Thu, Apr 12, 2012 at 04:24:35PM +0100, Andrew Haley wrote:
>> I found a couple of gforth bugs, FYI.
> ...
>> It's this bug, which returns the address of a local array:
>>
>> diff -r f14bc589172e prim
>> --- a/prim      Thu Apr 12 14:42:46 2012 +0100
>> +++ b/prim      Thu Apr 12 14:51:21 2012 +0100
>> @@ -1950,7 +1950,7 @@
>>
>>  newline        ( -- c_addr u ) gforth
>>  ""String containing the newline sequence of the host OS""
>> -char newline[] = {
>> +static const char newline[] = {
>>  #if DIRSEP=='/'
>>  /* Unix */
>>  '\n'
> 
> Thanks.  Why do you think that this is a bug in Gforth and not in gcc?

I think it's returning the address of a local string that is in
a block that has been exited.

>> We might as well also fix this other bug, which prevents the disassembler 
>> from
>> working:
>>
>> diff -r f14bc589172e dis-gdb.fs
>> --- a/dis-gdb.fs        Thu Apr 12 14:42:46 2012 +0100
>> +++ b/dis-gdb.fs        Thu Apr 12 14:51:21 2012 +0100
>> @@ -25,7 +25,7 @@
>>  : disasm-gdb { addr u -- }
>>      base @ >r hex
>>      s\" type mktemp >/dev/null && type gdb >/dev/null && file=`mktemp -t 
>> gforthdis.XXXXXXXXXX` && file2=`mktemp -t gforthdis.XXXXXXXXXX` && echo 
>> \"set verbose off\nset logging file $file\nset logging on\ndisas " save-mem 
>> ( addr u addr1 u1 )
>> -    addr 0 <<# bl hold # #s 'x hold # #> append-extend-string #>>
>> +    addr 0 <<# bl hold ',' hold # #s 'x hold # #> append-extend-string #>>
>>      addr u + 0 <<# # #s 'x hold # #> append-extend-string #>>
>>      r> base ! cr
>>      s\" \nset logging off\nquit\n\" >$file2 && gdb -nx -q -p `ps -p $$ -o 
>> ppid=` -x $file2 2>/dev/null >/dev/null && rm $file2 && grep -v \"of 
>> assembler\" $file && rm $file" append-extend-string
> 
> This is from an incompatible syntax change in gdb 7.1.  With this
> patch, gforth will no longer work with gdb 7.0 and earlier.  The
> workaround for that is:
> 
> http://www.complang.tuwien.ac.at/viewcvs/cgi-bin/viewcvs.cgi/gforth/dis-gdb.fs?r1=1.13&r2=1.8&makepatch=1&diff_format=h

Ohh, yuck.

Andrew.