[klibc] [klibc:master] klcc: Force make to use a shell to run 'command'

[klibc-bot for Ben Hutchings]

Commit-ID:  7e60022568f727fd264e796a10ce154486a3c56c
Gitweb:     http://git.kernel.org/?p=libs/klibc/klibc.git;a=commit;h=7e60022568f727fd264e796a10ce154486a3c56c
Author:     Ben Hutchings <ben at decadent.org.uk>
AuthorDate: Sat, 12 Dec 2020 22:17:50 +0100
Committer:  Ben Hutchings <ben at decadent.org.uk>
CommitDate: Sat, 12 Dec 2020 22:17:50 +0100

[klibc] klcc: Force make to use a shell to run 'command'

GNU make has an optimisation to run some commands without using the
shell, and its rules for recognising whether the shell is needed can
be buggy.

In particular, older versions don't recognise that 'command' may be a
shell built-in, and try to run it as if it's an external command.  Add
a redirection to the commamd line, to inhibit this optimisation.

Reported-by: Greg Thelen <gthelen at google.com>
References: https://lists.zytor.com/archives/klibc/2020-September/004548.html
References: https://git.kernel.org/linus/913ab9780fc021298949cc5514d6255a008e69f9
Signed-off-by: Ben Hutchings <ben at decadent.org.uk>

---
 klcc/Kbuild | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/klcc/Kbuild b/klcc/Kbuild
index ca46c6ce..82ca0e84 100644
--- a/klcc/Kbuild
+++ b/klcc/Kbuild
@@ -36,7 +36,7 @@ targets := $(KLIBCCROSS)klcc
 quiet_cmd_klcc = GEN     $@
       cmd_klcc = $(PERL) $< $(srctree)/$(src)/klcc.in \
                             $(obj)/$(KLIBCCROSS)klibc.config \
-                            $(shell command -v $(PERL)) \
+                            $(shell command -v $(PERL) 2>/dev/null) \
 			      > $@ || ( rm -f $@ ; exit 1 ) && \
 			      chmod a+x $@
 $(obj)/$(KLIBCCROSS)klcc: $(src)/makeklcc.pl $(src)/klcc.in \