Re: + git-klibc-mktemp-fix.patch added to -mm tree

Re: + git-klibc-mktemp-fix.patch added to -mm tree

[Sam Ravnborg]

On Sat, Apr 08, 2006 at 12:05:54AM -0700, akpm@osdl.org wrote:
> diff -puN usr/dash/mkbuiltins~git-klibc-mktemp-fix usr/dash/mkbuiltins
> --- 25/usr/dash/mkbuiltins~git-klibc-mktemp-fix	Sat Apr  8 14:51:11 2006
> +++ 25-akpm/usr/dash/mkbuiltins	Sat Apr  8 14:51:11 2006
> @@ -37,7 +37,7 @@
>  
>  tempfile=tempfile
>  if ! type tempfile > /dev/null 2>&1; then
> -	tempfile=mktemp
> +	tempfile="mktemp /tmp/tmp.XXXXXX"

Shouldn't that be:
> +	tempfile="$(mktemp /tmp/tmp.XXXXXX)"

	Sam

Re: + git-klibc-mktemp-fix.patch added to -mm tree

[H. Peter Anvin]

Sam Ravnborg wrote:
> On Sat, Apr 08, 2006 at 12:05:54AM -0700, akpm@osdl.org wrote:
>> diff -puN usr/dash/mkbuiltins~git-klibc-mktemp-fix usr/dash/mkbuiltins
>> --- 25/usr/dash/mkbuiltins~git-klibc-mktemp-fix	Sat Apr  8 14:51:11 2006
>> +++ 25-akpm/usr/dash/mkbuiltins	Sat Apr  8 14:51:11 2006
>> @@ -37,7 +37,7 @@
>>  
>>  tempfile=tempfile
>>  if ! type tempfile > /dev/null 2>&1; then
>> -	tempfile=mktemp
>> +	tempfile="mktemp /tmp/tmp.XXXXXX"
> 
> Shouldn't that be:
>> +	tempfile="$(mktemp /tmp/tmp.XXXXXX)"
> 

No, it's invoked later on as:

temp=$($tempfile)
temp2=$($tempfile)

Either which way; I have a better fix for the bison issue (this all has 
to do with the fact that make's handling of tools that output more than 
one file at a time is at the very best insane); however, I'm getting 
rather unhappy with some of the code in dash.

In particular, mksyntax.c seems to assume it runs on the same machine 
that the resulting code is going to execute on, for example, it tries to 
detect whether or not "char" is signed, but that doesn't work when 
cross-compiling.

dash isn't actually necessary in the in-kernel build, although it's a 
very nice bonus for customizing initramfs to have a shell to glue things 
together with.

Herbert: can the code be restructured with appropriate casts so that 
signed/unsigned is factored out of mksyntax?  As it currently stands, 
it's not cross-compile-safe, which is unacceptable.

	-hpa

Re: + git-klibc-mktemp-fix.patch added to -mm tree

[Bodo Eggert]

Sam Ravnborg <sam@ravnborg.org> wrote:
> On Sat, Apr 08, 2006 at 12:05:54AM -0700, akpm@osdl.org wrote:

>> diff -puN usr/dash/mkbuiltins~git-klibc-mktemp-fix usr/dash/mkbuiltins
>> --- 25/usr/dash/mkbuiltins~git-klibc-mktemp-fix      Sat Apr  8 14:51:11 2006
>> +++ 25-akpm/usr/dash/mkbuiltins      Sat Apr  8 14:51:11 2006

>> -    tempfile=mktemp
>> +    tempfile="mktemp /tmp/tmp.XXXXXX"
> 
> Shouldn't that be:
>> +    tempfile="$(mktemp /tmp/tmp.XXXXXX)"

No. You should use tempfile="$(mktemp ${TMPDIR:-/tmp}/tmp.XXXXXX)"
(or mktemp -t, if it's portable enough)

Besides that, tmp.XXXXXX should be replayed using a better name.

</nitpick>
-- 
Ich danke GMX dafür, die Verwendung meiner Adressen mittels per SPF
verbreiteten Lügen zu sabotieren.

Re: + git-klibc-mktemp-fix.patch added to -mm tree

[Herbert Xu]

On Sat, Apr 08, 2006 at 01:27:06PM -0700, H. Peter Anvin wrote:
>
> Herbert: can the code be restructured with appropriate casts so that 
> signed/unsigned is factored out of mksyntax?  As it currently stands, 
> it's not cross-compile-safe, which is unacceptable.

Sure, I'll send you a patch to convert it to always use unsigned char.
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

Re: + git-klibc-mktemp-fix.patch added to -mm tree

[Keith Owens]

"H. Peter Anvin" (on Sat, 08 Apr 2006 13:27:06 -0700) wrote:
>Either which way; I have a better fix for the bison issue (this all has 
>to do with the fact that make's handling of tools that output more than 
>one file at a time is at the very best insane)

Hit the same problem back in the 2.5 kbuild days, and worked around it
with some dummy dependency rules.  Like this one for bison/yacc.

side_effect(aicasm_gram.tab.h aicasm_gram.tab.c)

which expands to

$(objtree)/aicasm_gram.tab.h: $objtree/aicasm_gram.tab.c
	@/bin/true

That forces make to wait until aicasm_gram.tab.c is built before using
aicasm_gram.tab.h, and allows the following code to depend on either
aicasm_gram.tab.h or aicasm_gram.tab.c without any races.  The command
should not get executed, but you still need a command to keep make
happy.

Re: + git-klibc-mktemp-fix.patch added to -mm tree

[H. Peter Anvin]

Keith Owens wrote:
> "H. Peter Anvin" (on Sat, 08 Apr 2006 13:27:06 -0700) wrote:
>> Either which way; I have a better fix for the bison issue (this all has 
>> to do with the fact that make's handling of tools that output more than 
>> one file at a time is at the very best insane)
> 
> Hit the same problem back in the 2.5 kbuild days, and worked around it
> with some dummy dependency rules.  Like this one for bison/yacc.
> 
> side_effect(aicasm_gram.tab.h aicasm_gram.tab.c)
> 
> which expands to
> 
> $(objtree)/aicasm_gram.tab.h: $objtree/aicasm_gram.tab.c
> 	@/bin/true
> 
> That forces make to wait until aicasm_gram.tab.c is built before using
> aicasm_gram.tab.h, and allows the following code to depend on either
> aicasm_gram.tab.h or aicasm_gram.tab.c without any races.  The command
> should not get executed, but you still need a command to keep make
> happy.

A better way to do it for something like yacc/bison is to use a pattern 
rule.  Having two things on the LHS means different things for explicit 
and for pattern rules!

	-hpa