On 2004.4.30, at 04:38 PM, Sherm Pendley wrote:
> On Apr 30, 2004, at 2:30 AM, Joel Rees wrote:
>
>> My experience is that this kind of thing tends to lead to dead code >> or endless loops. Do I need to dig in and find the macro declaration >> and see if I can fix it?
>>
>> warning: comparison is always false due to limited range of data >> type
>
> In my own code, I compile with -Wall and try to chase down and > eliminate all warnings. Occasionally I might use a -Wno-something to > turn off a warning once I've determined that it's harmless, but I > really, really prefer to fix them.
Me too.
> I treat other people's code differently. If I'm building something > from source and it emits warnings, I'll make a mental note of that > fact. Then, if it's crashy, buggy, or exhibits some other odd > behavior, I might go back and see if the warnings are relevant to the > problems. If the app works fine though, I don't worry about the > warnings.
That's kind of what I was figuring would do, but I also would prefer not to find my code skipping a parse because the code got thrown out. So I thought I'd check.
> Those file names look familiar - are you building Perl?
Of course! (I suppose I should have said so.)
> If so, and the self-tests pass,
Well, since you're kind enough to ask (heh heh), here's a few more I get:
In the make phase,
...
cc -flat_namespace -L/usr/local/lib -o miniperl ¥
miniperlmain.o opmini.o libperl.a -lm -lc
./miniperl -w -Ilib -MExporter -e '<?>' || make minitest
make: [extra.pods] Error 1 (ignored)
./miniperl -Ilib configpm configpm.tmp
sh mv-if-diff configpm.tmp lib/Config.pm
...
Making Errno (nonxs)
Writing Makefile for Errno
../../miniperl "-I../../lib" "-I../../lib" "-I../../lib" "-I../../lib" Errno_pm.PL Errno.pm
cp Errno.pm ../../lib/Errno.pm
make: [extras.make] Error 1 (ignored)
Everything is up to date. Type 'make test' to run test suite.
and also the range warnings mentioned already. In the make test phase,
...
ext/DB_File/t/db-btree...............#
# This test is known to crash in Mac OS X versions 10.2 (or earlier)
# because of the buggy Berkeley DB version included with the OS.
#
FAILED at test 0
ext/DB_File/t/db-hash................ok
ext/DB_File/t/db-recno...............#
# Some older versions of Berkeley DB version 1 will fail db-recno
# tests 61, 63, 64 and 65.
...
# You can safely ignore the errors if you're never going to use the
...
#
FAILED at test 64
ext/Devel/DProf/t/DProf..............ok
...
Failed 2 test scripts out of 804, 99.75% okay.
### Since not all tests were successful, you may want to run some of
...
### Bourne-style shells, like bash, ksh, and zsh, respectively.
u=25.78 s=0 cu=599.71 cs=171.77 scripts=804 tests=80310
make[2]: *** [_test_tty] Error 1
make[1]: *** [_test] Error 2
make: *** [test] Error 2
It says I can ignore those, so I did a make install and got
...
Making Errno (nonxs)
make[1]: [extras.make] Error 1 (ignored)
Everything is up to date. Type 'make test' to run test suite.
if [ -n "" ]; ¥
then ¥
cd utils; make compile; ¥
cd ../x2p; make compile; ¥
cd ../pod; make compile; ¥
else :; ¥
fi
./perl installperl --destdir=
WARNING: You've never run 'make test' or some tests failed! (Installing anyway.)
which worried me a little. So I went ahead and ran t/harness after the install completed. (That's backwards, I suppose.):
...
op/lex_assign..........................ok
op/lfs.................................skipped
all skipped: writing past 2GB failed: process limits?
op/list................................ok
...
../ext/DB_File/t/db-btree..............#
# This test is known to crash in Mac OS X versions 10.2 (or earlier)
# because of the buggy Berkeley DB version included with the OS.
#
../ext/DB_File/t/db-btree..............dubious
Test returned status 0 (wstat 10, 0xa)
../ext/DB_File/t/db-hash...............ok
../ext/DB_File/t/db-recno..............#
# Some older versions of Berkeley DB version 1 will fail db-recno
# tests 61, 63, 64 and 65.
#
# For example Mac OS X 10.2 (or earlier) has such an old
...
../ext/DB_File/t/db-recno..............FAILED tests 64, 67, 70
Failed 3/191 tests, 98.43% okay
../ext/Devel/DProf/t/DProf.............ok
...
../ext/Fcntl/t/syslfs..................skipped
all skipped: writing past 2GB failed: process limits?
../ext/File/Glob/t/basic...............ok
...
Failed Test Stat Wstat Total Fail Failed List of Failed
------------------------------------------------------------------------ -------
../ext/DB_File/t/db-btree.t 0 10 ?? ?? % ??
../ext/DB_File/t/db-recno.t 191 3 1.57% 64 67 70
59 tests and 486 subtests skipped.
Failed 2/868 test scripts, 99.77% okay. 3/80321 subtests failed, 100.00% okay.
Which I suppose looks pretty good, really, since the BDB stuff requires getting some good libraries, etc. But I did get some stuff skipped that I wanted to ask about, as well.
> I definitely wouldn't worry about the warnings too much. Perl's > self-tests are remarkably thorough.
Anyway, I guess I was wondering how important those range warnings were likely to be.
Joel Rees
- Re: "comparison always false" is a problem or not? Joel Rees
- Re: "comparison always false" is a problem or... Sherm Pendley