Re: Broken world in rtld-elf...
On Thu, 13 Jun 2002, Alex Zepeda wrote: On Thu, Jun 13, 2002 at 12:26:05PM +1000, Bruce Evans wrote: rtld still uses asms with the old, broken/fragile 0 constraint. This constraint is especially broken/fragile if things are pessimized by compiling without optimizations. D'oh! Is there any chance of sticking a warning in the makefile if -O0 (or whatever else would cause it to not compile) is present? Not really. It is a transient bug that is almost as easy to fix as warn about. Bruce To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-current in the body of the message
Re: Broken world in rtld-elf...
On Fri, Jun 14, 2002 at 07:09:06PM +1000, Bruce Evans wrote: Not really. It is a transient bug that is almost as easy to fix as warn about. So when can I expect the fix to be committed? :-D - alex To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-current in the body of the message
Re: Broken world in rtld-elf...
On Thu, Jun 13, 2002 at 12:26:05PM +1000, Bruce Evans wrote: rtld still uses asms with the old, broken/fragile 0 constraint. This constraint is especially broken/fragile if things are pessimized by compiling without optimizations. D'oh! Is there any chance of sticking a warning in the makefile if -O0 (or whatever else would cause it to not compile) is present? - alex To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-current in the body of the message
Re: Broken world in rtld-elf...
Alex Zepeda wrote:
On Thu, Jun 13, 2002 at 12:26:05PM +1000, Bruce Evans wrote:
rtld still uses asms with the old, broken/fragile 0 constraint. This
constraint is especially broken/fragile if things are pessimized by
compiling without optimizations.
D'oh!
Is there any chance of sticking a warning in the makefile if -O0 (or
whatever else would cause it to not compile) is present?
GCCVERS=`gcc -v 21 | grep version | cut -d -f 3`
.if ${GCCVERS} = 3.1
.BEGIN:
echo Optimization with GCC 3.1 is often broken! 2
.endif
Oh... you wanted to grep -O out of the CFLAGS and CXXFLAGS?
How to do that should be obvious from the above...
-- Terry
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Re: Broken world in rtld-elf...
* Terry Lambert [EMAIL PROTECTED] escriurères
Alex Zepeda wrote:
On Thu, Jun 13, 2002 at 12:26:05PM +1000, Bruce Evans wrote:
rtld still uses asms with the old, broken/fragile 0 constraint. This
constraint is especially broken/fragile if things are pessimized by
compiling without optimizations.
D'oh!
Is there any chance of sticking a warning in the makefile if -O0 (or
whatever else would cause it to not compile) is present?
GCCVERS=`gcc -v 21 | grep version | cut -d -f 3`
.if ${GCCVERS} = 3.1
.BEGIN:
echo Optimization with GCC 3.1 is often broken! 2
.endif
Oh... you wanted to grep -O out of the CFLAGS and CXXFLAGS?
How to do that should be obvious from the above...
Errr, it was with 0 level optimisation that is the problem, not a real
level. Read carefully what bde said, and look at hte warnings and how
GCC deals with the code in question.
Also, your example is very wrong, read make(1)'s section on dealing with
variables.
--
Juli Mallett [EMAIL PROTECTED] FreeBSD: The Power To Serve
Perception is prejudice / Don't classify me / Accept me as me / Not what you see
To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message
Re: Broken world in rtld-elf...
Juli Mallett wrote: Errr, it was with 0 level optimisation that is the problem, not a real level. Read carefully what bde said, and look at hte warnings and how GCC deals with the code in question. Also, your example is very wrong, read make(1)'s section on dealing with variables. I know my example is very wrong; though it could be used to grep for optimizer flags, where it could not be used for what I jokingly said it could be used for... I guess it was too subtle. Question: -O0 fails to produce good code; how do I check and warn if -O0 is being used? Answer: Fix -O0, or grep its use and complain about it Answer 2: Make its use an argument error to the compiler, until it is fixed Answer 3: Quit munging the Makefiles, when they will just need to be unmunged later, and the problem goes away if you change the compiler -- Terry To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-current in the body of the message
Re: Broken world in rtld-elf...
* Terry Lambert [EMAIL PROTECTED] escriurères
Juli Mallett wrote:
Errr, it was with 0 level optimisation that is the problem, not a real
level. Read carefully what bde said, and look at hte warnings and how
GCC deals with the code in question.
Also, your example is very wrong, read make(1)'s section on dealing with
variables.
I know my example is very wrong; though it could be used to grep
for optimizer flags, where it could not be used for what I jokingly
said it could be used for... I guess it was too subtle.
Question:
-O0 fails to produce good code; how do I check and warn if
-O0 is being used?
Answer:
Fix -O0, or grep its use and complain about it
.if ${MACHINE_ARCH} == i386
CFLAGS:= $(CFLAGS:N-O0)
.endif
I think.
Answer 2:
Make its use an argument error to the compiler, until it is
fixed
-O0 isn't broken, it just doesn't handle this construct right, and the issue
is known.
Answer 3:
Quit munging the Makefiles, when they will just need to be
unmunged later, and the problem goes away if you change
the compiler
NetBSD and OpenBSD do this to work around crappy toolchains all the time.
Most of the time it's to *enable* -O0 though, ironically :)
--
Juli Mallett [EMAIL PROTECTED] FreeBSD: The Power To Serve
Perception is prejudice / Don't classify me / Accept me as me / Not what you see
To Unsubscribe: send mail to [EMAIL PROTECTED]
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Re: Broken world in rtld-elf...
On Wed, 12 Jun 2002, Alex Zepeda wrote: So what's up with -current? I had to install gawk to get the kernel to build (and world too for that matter).. I haven't had the balls to put the one true awk back in place. But now whether in world mode or not I get: blarf:/usr/src/libexec/rtld-elf#make cc -O0 -Wall -DFREEBSD_ELF -I/usr/src/libexec/rtld-elf/i386 ^^^ -I/usr/src/libexec/rtld-elf -elf -fpic -DPIC -Wformat=2 -Wno-format-extra-args -c /usr/src/libexec/rtld-elf/rtld.c /usr/src/libexec/rtld-elf/rtld.c: In function `atomic_decr_int': /usr/src/libexec/rtld-elf/i386/rtld_machdep.h:58: inconsistent operand constraints in an `asm' *** Error code 1 rtld still uses asms with the old, broken/fragile 0 constraint. This constraint is especially broken/fragile if things are pessimized by compiling without optimizations. Bruce To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-current in the body of the message
