On Wed, Feb 11, 2015 at 12:22 PM, Paul Smith <psm...@gnu.org> wrote:
> On Wed, 2015-02-11 at 10:44 -0800, David Boyce wrote:
> > I just noticed that while assigning to SHELL suppresses the fast-path
> > algorithm, assigning to .SHELLFLAGS does not. Feature or bug?
>
> That's a good question. I'm sort of agnostic on it. On one hand, it's
> hard to think of a flag added to SHELLFLAGS (given the default value of
> SHELL) that would matter for the fast path
>
Actually it gets weirder. Some values of .SHELLFLAGS suppress fast path,
others do not:
% cat makefile
foo:; @echo making $@
% strace -e process -q -f -- make-4.1 .SHELLFLAGS=-ec 2>&1 | grep 'execve.*
= 0'
[pid 23605] execve("/bin/echo", ["echo", "making", "foo"], [/* 46 vars */])
= 0
% strace -e process -q -f -- make-4.1 .SHELLFLAGS=-xc 2>&1 | grep 'execve.*
= 0'
[pid 23745] execve("/bin/sh", ["/bin/sh", "-xc", "echo making foo"], [/* 46
vars */]) = 0
The two straced invocations differ only in that one adds -e to .SHELLFLAGS
and the other adds -x.
Wait … ChangeLog.3 says:
(construct_command_argv_internal): If .SHELLFLAGS is non-standard
use the slow path. Use that value instead of hard-coded "-c”.
But apparently -c and -ec are both considered standard so I guess it works
as designed.
David
_______________________________________________
Bug-make mailing list
Bug-make@gnu.org
https://lists.gnu.org/mailman/listinfo/bug-make
