Re: GNU Make on Linux Feeding All Commands Through ksh

[Steve Waltner]

On Oct 8, 2008, at 1:16 PM, David Boyce wrote:
> On Wed, Oct 8, 2008 at 12:31 PM, Steve Waltner  
> <address@hidden> wrote:
> > - The makefiles include settings like "override SHELL = /bin/ksh"  
> > to force
> > all shell interpretations to go through the ksh.
> >
> > It appears as though the Linux system feeds every command through a  
> > ksh
> > process, while the same function on the Solaris system calls the  
> > command
> > (wether it is a ccpentium, ccarm, or make command) directly.
>
> Are you sure that SHELL = /bin/ksh setting is present on both
> platforms? Because the standard behavior of GNU make is to try to
> avoid using the shell (to "call the command directly") wherever
> possible, *unless* the value of $(SHELL) has been overridden. This is
> a good thing, because once the user has swapped in his own shell
> there's no way for make to know what its special characters, parsing
> rules, etc might be, so it skips the optimization and just throws the
> command line at the new value of $(SHELL).
>
> So, regardless of your Solaris/Linux and -j issues, the first mystery
> to be solved is why you are not seeing $(SHELL) be executed on
> Solaris. Is it possible you're using a strict-POSIX configuration of
> Solaris, wherein /bin/sh becomes the POSIX shell aka ksh, and have
> become reliant on that?
>
> David Boyce

I'll confess that I'm a little out of my element here. The make  
process we are using was developed over the last 15 years by a  
developer that recently left the company. I'm coming in as a System  
Administrator trying to fix it to where we can deploy Linux build  
hosts to all users. I do remember the developer saying something about  
setting $(SHELL) to get things parsed properly, but I don't know the  
details on why that was necessary.

From what I've gathered, SHELL is always set to /bin/ksh. There are a  
couple ifeq/ifneq checks in the makefiles to define things differently  
on Linux and Solaris, but I haven't traced how those could be wrapped  
around the definitions for setting SHELL. To confirm that statement, I  
edited the rule that spawns the make in each of the sub-directories as  
follows, which for non-verbose builds has $(Q) set to "@".  I added  
the "echo $(SHELL)" as a debug and this spits out numerous lines  
saying /bin/ksh when the build is run on either Solaris or Linux, but  
no blank lines (or /bin/sh lines either), so it appears to me to  
always be set.

============================
.PHONY: %.make
%.make:
        echo $(SHELL)
        +$(Q)$(MAKE) \
                -C $(patsubst %/,%,$(dir $@)) \
                $(basename $(notdir $@)) \
                $(subst $(_comma_),$(_space_),$(MKopts)) \
                MKLevel=$$(( $(MKLevel) + 1 ))
============================

I'm not following what your asking in your second paragraph. It sounds  
like you're suspecting that our Solaris build of GNU make possibly  
has /bin/ksh as the internal SHELL instead of /bin/sh. I don't believe  
that is true. In the following output ictgrid004 is a Solaris box and  
ictgrid005 is the Linux box...

============================
ictgrid004:~> which make
/soft/gnu/make/3.81/bin/make
ictgrid004:~> echo $SHELL
/bin/tcsh
ictgrid004:~> make -p | grep SHELL
make: *** No targets specified and no makefile found.  Stop.
SHELL = /bin/sh
ictgrid004:~>


ictgrid005:~> which make
/soft/gnu/make/3.81/bin/make
ictgrid005:~> echo $SHELL
/bin/tcsh
ictgrid005:~> make -p | grep SHELL
make: *** No targets specified and no makefile found.  Stop.
SHELL = /bin/sh
ictgrid005:~>
============================

We don't have anything funny like /bin/sh and /bin/ksh being the same  
binary either:

============================
ictgrid004:~> \ls -ld /bin /usr/bin/sh /usr/bin/ksh
lrwxrwxrwx   1 root     root           9 Jul 13  2006 /bin -> ./usr/bin
-r-xr-xr-x   3 root     bin       209268 Mar 27  2006 /usr/bin/ksh
-r-xr-xr-x   4 root     root       95480 Mar 25  2006 /usr/bin/sh
ictgrid004:~>


ictgrid005:~> \ls -ld /bin /bin/sh /bin/ksh /bin/bash
drwxr-xr-x  2 root root   4096 Sep 30 12:17 /bin
-rwxr-xr-x  1 root root 773184 Apr  1  2008 /bin/bash
-rwxr-xr-x  1 root root 217552 Jun 22  2007 /bin/ksh
lrwxrwxrwx  1 root root      4 Sep 30 10:29 /bin/sh -> bash
ictgrid005:~>
============================

Steve