make -C tools clean failure on older systems

PATCH Arnaldo Carvalho de Melo 3 participants 7 messages May 14, 2015 Kselftest

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Arnaldo Carvalho de Melo

author

2015-05-14 15:12 UTC #0 lore raw

Hi,

In:

-------------
commit 67d8712dcc70aa16d8e14a52eb73870e3cbddfc2

Author: Shuah Khan <[email protected]>
Date:   Wed Mar 18 11:57:39 2015 -0600

selftests: Fix build failures when invoked from kselftest target

-------------

You cleaned two variables using different methods, any reason for that?

I asked because the 'undefine' method causes it to fail in older systems:

[acme@rhel5 linux]$ make -C tools/ clean
<SNIP>
CLEAN python
make[1]: Leaving directory `/home/acme/git/linux/tools/perf'
DESCEND testing/selftests
make[1]: Entering directory /home/acme/git/linux/tools/testing/selftests' Makefile:30: *** missing separator. Stop. make[1]: Leaving directory /home/acme/git/linux/tools/testing/selftests'
make: *** [selftests_clean] Error 2
make: Leaving directory `/home/acme/git/linux/tools'

----------------------------------

[acme@rhel5 linux]$ make --version
GNU Make 3.81
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

This program built for x86_64-redhat-linux-gnu
[acme@rhel5 linux]$

Wonder if it would be ok to use:

tools/testing/selftests/Makefile +1 -1

index 95abddcd7839..f76830643086 100644
@@ -27,7 +27,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif

------------------------------------------

- Arnaldo

Shuah Khan

2015-05-14 15:39 UTC #1 lore raw

Quoted 9 lines · Arnaldo Carvalho de Melo

Hi,
	In:
-------------
commit 67d8712dcc70aa16d8e14a52eb73870e3cbddfc2
Author: Shuah Khan <[email protected]>
Date:   Wed Mar 18 11:57:39 2015 -0600

Quoted 8 lines

selftests: Fix build failures when invoked from kselftest target
-------------
You cleaned two variables using different methods, any reason for that?
I asked because the 'undefine' method causes it to fail in older systems:

The reason for this change is some tests fail to build when invoked from the main Makefile level. The commit log explains the change:

Several tests that rely on implicit build rules fail to build, when invoked from the main Makefile kselftest target. These failures are due to --no-builtin-rules and --no-builtin-variables options set in the inherited MAKEFLAGS.

--no-builtin-rules eliminates the use of built-in implicit rules and --no-builtin-variables is for not defining built-in variables. These two options override the use of implicit rules resulting in build failures. In addition, inherited LDFLAGS result in build failures and there is no need to define LDFLAGS. Clear LDFLAGS and MAKEFLAG when make is invoked from the main Makefile kselftest target. Fixing this at selftests Makefile avoids changing the main Makefile and keeps this change self contained at selftests level.

Quoted 33 lines

[acme@rhel5 linux]$ make -C tools/ clean
<SNIP>
CLEAN python
make[1]: Leaving directory `/home/acme/git/linux/tools/perf'
DESCEND testing/selftests
make[1]: Entering directory /home/acme/git/linux/tools/testing/selftests' Makefile:30: *** missing separator. Stop. make[1]: Leaving directory /home/acme/git/linux/tools/testing/selftests'
make: *** [selftests_clean] Error 2
make: Leaving directory `/home/acme/git/linux/tools'
----------------------------------
[acme@rhel5 linux]$ make --version
GNU Make 3.81
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
This program built for x86_64-redhat-linux-gnu
[acme@rhel5 linux]$
Wonder if it would be ok to use:
tools/testing/selftests/Makefile +0 -0
index 95abddcd7839..f76830643086 100644

tools/testing/selftests/Makefile TARGETS_HOTPLUG += memory-hotplug · line 32

Quoted 7 lines

tools/testing/selftests/Makefile +1 -1

@@ -27,7 +27,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif

I recall testing with override and remember it to not work. If you would like experiment with it, feel free to send a patch with that change. My make version is very new:

make --version
GNU Make 4.0
Built for x86_64-pc-linux-gnu

You have to run make kselftest from the main kernel Makefile to see the build failures that undefine LDFLAGS fixed.

thanks,
-- Shuah

Signature · 5 lines

Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America (Silicon Valley)
[email protected] | (970) 217-8978

Arnaldo Carvalho de Melo

author

2015-05-14 15:54 UTC #2 lore raw

Em Thu, May 14, 2015 at 09:39:43AM -0600, Shuah Khan escreveu:

Quoted 14 lines · Arnaldo Carvalho de Melo

Quoted 13 lines
Hi,
	In:
-------------
commit 67d8712dcc70aa16d8e14a52eb73870e3cbddfc2
Author: Shuah Khan <[email protected]>
Date:   Wed Mar 18 11:57:39 2015 -0600
selftests: Fix build failures when invoked from kselftest target
-------------

Quoted 7 lines

Quoted 4 lines
You cleaned two variables using different methods, any reason for that?
I asked because the 'undefine' method causes it to fail in older systems:
The reason for this change is some tests fail to build when invoked from the main Makefile level. The commit log explains the change:

I saw it

Quoted 11 lines

tools/testing/selftests/Makefile TARGETS_HOTPLUG += memory-hotplug · line 32
Quoted 9 lines
+++ b/tools/testing/selftests/Makefile
tools/testing/selftests/Makefile +1 -1
@@ -27,7 +27,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif
I recall testing with override and remember it to not work. If you would

bummer, then its not that easy, I thought it was an oversight, but if you tested it and it didn't work, nevermind, no need, I guess, to support older systems if it requires more, non trivial, work.

Quoted 21 lines

like experiment with it, feel free to send a patch with that change. My make version is very new:
make --version
GNU Make 4.0
Built for x86_64-pc-linux-gnu
You have to run make kselftest from the main kernel Makefile to see the build failures that undefine LDFLAGS fixed.
thanks,
-- Shuah
Signature · 5 lines
Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America (Silicon Valley)
[email protected] | (970) 217-8978

Ingo Molnar

2015-05-14 17:42 UTC #3 lore raw

Quoted 11 lines · Arnaldo Carvalho de Melo

Quoted 10 lines
tools/testing/selftests/Makefile TARGETS_HOTPLUG += memory-hotplug · line 32
Quoted 8 lines
tools/testing/selftests/Makefile +1 -1
@@ -27,7 +27,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif
I recall testing with override and remember it to not work. If you would

Quoted 3 lines

bummer, then its not that easy, I thought it was an oversight, but if you tested it and it didn't work, nevermind, no need, I guess, to support older systems if it requires more, non trivial, work.

So what's the 'make' version cutoff for this capability?

We should not require insane hacks, the minimum required make version for the kernel, as per Documentation/Changes, is v3.80:

o GNU make 3.80 # make --version

Thanks,

Ingo

Arnaldo Carvalho de Melo

author

2015-05-14 20:00 UTC #4 lore raw

Em Thu, May 14, 2015 at 07:42:22PM +0200, Ingo Molnar escreveu:

Quoted 13 lines · Arnaldo Carvalho de Melo

Quoted 11 lines
Quoted 7 lines
tools/testing/selftests/Makefile TARGETS_HOTPLUG += memory-hotplug · line 31
Quoted 5 lines
# Makefile doesn't have explicit build rules.
ifeq (1,$(MAKELEVEL))
tools/testing/selftests/Makefile +1 -1
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
I recall testing with override and remember it to not work. If you would
bummer, then its not that easy, I thought it was an oversight, but if you tested it and it didn't work, nevermind, no need, I guess, to support older systems if it requires more, non trivial, work.

Quoted 6 lines

So what's the 'make' version cutoff for this capability?
We should not require insane hacks, the minimum required make version for the kernel, as per Documentation/Changes, is v3.80:
o GNU make 3.80 # make --version

3.81 is what is used where I found the problem.

With his confirmation that one of the two variants that he used on the same patch to do what seemingly has the same effect for the problem at hand, the one that is supported in make 3.81 (RHEL5), all is well :-)

- Arnaldo

Shuah Khan

2015-05-14 18:29 UTC #5 lore raw

In reply to Arnaldo Carvalho de Melo

Quoted 37 lines · Arnaldo Carvalho de Melo

Em Thu, May 14, 2015 at 09:39:43AM -0600, Shuah Khan escreveu:
Quoted 14 lines · Arnaldo Carvalho de Melo
Quoted 13 lines
Hi,
	In:
-------------
commit 67d8712dcc70aa16d8e14a52eb73870e3cbddfc2
Author: Shuah Khan <[email protected]>
Date:   Wed Mar 18 11:57:39 2015 -0600
selftests: Fix build failures when invoked from kselftest target
-------------
Quoted 7 lines
Quoted 4 lines
You cleaned two variables using different methods, any reason for that?
I asked because the 'undefine' method causes it to fail in older systems:
The reason for this change is some tests fail to build when invoked from the main Makefile level. The commit log explains the change:
I saw it
Quoted 11 lines
Review TARGETS_HOTPLUG += memory-hotplug · line 32
Quoted 9 lines
+++ b/tools/testing/selftests/Makefile
(quoted diff) +1 -1
@@ -27,7 +27,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif
I recall testing with override and remember it to not work. If you would

Quoted 14 lines

bummer, then its not that easy, I thought it was an oversight, but if you tested it and it didn't work, nevermind, no need, I guess, to support older systems if it requires more, non trivial, work.
Quoted 10 lines
like experiment with it, feel free to send a patch with that change. My make version is very new:
make --version
GNU Make 4.0
Built for x86_64-pc-linux-gnu
You have to run make kselftest from the main kernel Makefile to see the build failures that undefine LDFLAGS fixed.

Hmm. I ran a quick test with override and it worked. My recollection must not be good. :) Here is what I tried:

(quoted diff) +0 -0

b/tools/testing/selftests/Makefile
index ebac6b8..56b11cd 100644

tools/testing/selftests/Makefile +1 -1

@@ -28,7 +28,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif

Could you please try this and let me know if it works and if you have time, please send me a patch as well.

thanks,
-- Shuah

Signature · 5 lines

Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America (Silicon Valley)
[email protected] | (970) 217-8978

Arnaldo Carvalho de Melo

author

2015-05-14 19:48 UTC #6 lore raw

Em Thu, May 14, 2015 at 12:29:37PM -0600, Shuah Khan escreveu:

Quoted 62 lines · Arnaldo Carvalho de Melo

Quoted 37 lines
Em Thu, May 14, 2015 at 09:39:43AM -0600, Shuah Khan escreveu:
Quoted 14 lines · Arnaldo Carvalho de Melo
Quoted 13 lines
Hi,
	In:
-------------
commit 67d8712dcc70aa16d8e14a52eb73870e3cbddfc2
Author: Shuah Khan <[email protected]>
Date:   Wed Mar 18 11:57:39 2015 -0600
selftests: Fix build failures when invoked from kselftest target
-------------
Quoted 7 lines
Quoted 4 lines
You cleaned two variables using different methods, any reason for that?
I asked because the 'undefine' method causes it to fail in older systems:
The reason for this change is some tests fail to build when invoked from the main Makefile level. The commit log explains the change:
I saw it
Quoted 11 lines
tools/testing/selftests/Makefile TARGETS_HOTPLUG += memory-hotplug · line 32
Quoted 9 lines
+++ b/tools/testing/selftests/Makefile
tools/testing/selftests/Makefile +1 -1
@@ -27,7 +27,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif
I recall testing with override and remember it to not work. If you would
Quoted 14 lines
bummer, then its not that easy, I thought it was an oversight, but if you tested it and it didn't work, nevermind, no need, I guess, to support older systems if it requires more, non trivial, work.
Quoted 10 lines
like experiment with it, feel free to send a patch with that change. My make version is very new:
make --version
GNU Make 4.0
Built for x86_64-pc-linux-gnu
You have to run make kselftest from the main kernel Makefile to see the build failures that undefine LDFLAGS fixed.
Hmm. I ran a quick test with override and it worked. My recollection must not be good. :) Here is what I tried:
tools/testing/selftests/Makefile +0 -0
index ebac6b8..56b11cd 100644

tools/testing/selftests/Makefile TARGETS_HOTPLUG += memory-hotplug · line 33

Quoted 7 lines

tools/testing/selftests/Makefile +1 -1

@@ -28,7 +28,7 @@ TARGETS_HOTPLUG += memory-hotplug
 # Makefile to avoid test build failures when test
 # Makefile doesn't have explicit build rules.
 ifeq (1,$(MAKELEVEL))
-undefine LDFLAGS
+override LDFLAGS =
 override MAKEFLAGS =
 endif

Yeah, that is perfect! I.e. it is the patch I had proposed :o)

Ok, will send a patch to you, works well for me for:

Red Hat Enterprise Linux 5 (Fedora Core 6 based, ides of 2.6.18 kernels)

[acme@rhel5 tools]$ make -v
GNU Make 3.81

And:

Fedora 21:

[acme@zoo tools]$ make --version
GNU Make 4.0

- Arnaldo