[Buildroot] [PATCHv5 0/2] Detect incorrect dependencies

[Buildroot] [PATCHv5 0/2] Detect incorrect dependencies

[Thomas Petazzoni]

Hello,

This is the fifth version of the small patch series to detect
incorrect dependencies (i.e a package that depends on another in its
.mk file, but that forgets to do so in its Config.in).

Compared to the previous version, this new version:

 - Use $($(PKG)_TYPE) and $($(PKG)_KCONFIG)_VAR) instead of
   target-specific variables, as suggested by Arnout.

 - Move the "culprit listing" logic into a separate patch, so that it
   can be considered separately, suggested by Yann E. Morin.

 - Makes some other trivial adjustements suggested by Yann and Arnout.

 - Is rebased on top of master.

Thanks,

Thomas

Thomas Petazzoni (2):
  pkg-generic: detect incorrectly used package
  pkg-generic: improve incorrectly used package detection

 package/pkg-generic.mk | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

-- 
2.6.1

[Buildroot] [PATCHv5 1/2] pkg-generic: detect incorrectly used package

[Thomas Petazzoni]

In Buildroot, the selection of a package from a Config.in level and
from a Makefile level are completely disconnected. This can lead to
issues where the build of a package is triggered at the Makefile level
due to the package being listed in another package <pkg>_DEPENDENCIES
variable, even if that package is not enabled in the configuration.

This has for example been the case recently with python-can having
'python' in its <pkg>_DEPENDENCIES, while python-can could be enabled
when Python 3.x is used, in which case the 'python' package should not
be built.

To detect such issues more easily, this patch adds a check in the
package infrastructure. When the build process of a package is being
triggered, we verify that the package is enabled in the
configuration. We do this check in the "configure" step, since this
step is the first common step between the normal download case and the
"local site method" / "package override" case.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
Changes since v4:
 - Use $($(PKG)_KCONFIG_VAR) and $($(PKG)_TYPE) as suggested by Arnout.
 - Split the "potential culprit" mechanism into a separate commit, as
   suggested by Yann.

Changes since v3:
 - Add the DEPENDENT_OF mechanism to display which packages are
   mistakenly depending on a package without selecting it. Suggested
   and implement by Yann E. Morin.

Changes since v2:
 - Only do the check if MAKECMDGOALS is empty, i.e if a "default"
   build is being done. This allows advanced users to continue doing
   "make <pkg>" to forcefully build a package even if not enabled in
   the configuration. Suggested by Peter Korsgaard.
 - Add @ in front of the test command so that it doesn't get
   displayed. Suggested by Peter Korsgaard.
 - Improve error message, as suggested by Peter Korsgaard.

Changes since v1:
 - Use KCONFIG_VAR in order to make the thing work for toolchain
   packages, bootloaders and Linux. Issue reported by Vicente.
---
 package/pkg-generic.mk | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
index 76ec295..a831199 100644
--- a/package/pkg-generic.mk
+++ b/package/pkg-generic.mk
@@ -143,6 +143,16 @@ $(foreach dir,$(call qstrip,$(BR2_GLOBAL_PATCH_DIR)),\
 
 # Configure
 $(BUILD_DIR)/%/.stamp_configured:
+# Only trigger the check for default builds. If the user forces
+# building a package, even if not enabled in the configuration, we
+# want to accept it.
+ifeq ($(MAKECMDGOALS),)
+	@if test "$($(PKG)_TYPE)" = "target" -a -z "$($($(PKG)_KCONFIG_VAR))" ; then \
+		echo "ERROR: A package must have added $($(PKG)_NAME) to its _DEPENDENCIES line but" ; \
+		echo "forgot to add the corresponding select / depends on $($(PKG)_KCONFIG_VAR)." ; \
+		exit 1 ; \
+	fi
+endif
 	@$(call step_start,configure)
 	@$(call MESSAGE,"Configuring")
 	$(foreach hook,$($(PKG)_PRE_CONFIGURE_HOOKS),$(call $(hook))$(sep))
-- 
2.6.1

[Buildroot] [PATCHv5 2/2] pkg-generic: improve incorrectly used package detection

[Thomas Petazzoni]

The package infrastructure now detects when a target package is being
built even if its corresponding Config.in option is not enabled, and
aborts with an error. However, it does not indicate *which* package is
improperly depending on the current package without selecting it at
the kconfig level.

So, in this commit, in addition to displaying an error, we try to help
the user by saying which packages could be the culprit. To achieve
this, we register the reverse dependencies of each package in a
variable called <pkg>_DEPENDENT_OF, and display this variable for the
problematic package when the error is detected. Many thanks to Yann
E. Morin for the idea and implementation!

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 package/pkg-generic.mk | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
index a831199..1266a47 100644
--- a/package/pkg-generic.mk
+++ b/package/pkg-generic.mk
@@ -150,6 +150,8 @@ ifeq ($(MAKECMDGOALS),)
 	@if test "$($(PKG)_TYPE)" = "target" -a -z "$($($(PKG)_KCONFIG_VAR))" ; then \
 		echo "ERROR: A package must have added $($(PKG)_NAME) to its _DEPENDENCIES line but" ; \
 		echo "forgot to add the corresponding select / depends on $($(PKG)_KCONFIG_VAR)." ; \
+		echo "Potential culprits:" ; \
+		for p in $($(PKG)_DEPENDENT_OF) ; do echo " - $$p" ; done ; \
 		exit 1 ; \
 	fi
 endif
@@ -777,6 +779,12 @@ endif # ifneq ($$(call qstrip,$$($(2)_SOURCE)),)
 # configuration
 ifeq ($$($$($(2)_KCONFIG_VAR)),y)
 
+# Store reverse build-dependency information: we add the name of the
+# current package to the <pkg>_DEPENDENT_OF variable of all packages
+# the current package depends on.
+$$(eval $$(foreach d,$$($(2)_FINAL_ALL_DEPENDENCIES),\
+	$$(call UPPERCASE,$$(d))_DEPENDENT_OF += $(1)$$(sep)))
+
 # Ensure the calling package is the declared provider for all the virtual
 # packages it claims to be an implementation of.
 ifneq ($$($(2)_PROVIDES),)
-- 
2.6.1

[Buildroot] [PATCHv5 2/2] pkg-generic: improve incorrectly used package detection

[Yann E. MORIN]

Thomas, All,

On 2015-10-09 11:15 +0200, Thomas Petazzoni spake thusly:
> The package infrastructure now detects when a target package is being
> built even if its corresponding Config.in option is not enabled, and
> aborts with an error. However, it does not indicate *which* package is
> improperly depending on the current package without selecting it at
> the kconfig level.
> 
> So, in this commit, in addition to displaying an error, we try to help
> the user by saying which packages could be the culprit. To achieve
> this, we register the reverse dependencies of each package in a
> variable called <pkg>_DEPENDENT_OF, and display this variable for the
> problematic package when the error is detected. Many thanks to Yann
> E. Morin for the idea and implementation!
> 
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
>  package/pkg-generic.mk | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
> index a831199..1266a47 100644
> --- a/package/pkg-generic.mk
> +++ b/package/pkg-generic.mk
> @@ -150,6 +150,8 @@ ifeq ($(MAKECMDGOALS),)
>  	@if test "$($(PKG)_TYPE)" = "target" -a -z "$($($(PKG)_KCONFIG_VAR))" ; then \
>  		echo "ERROR: A package must have added $($(PKG)_NAME) to its _DEPENDENCIES line but" ; \
>  		echo "forgot to add the corresponding select / depends on $($(PKG)_KCONFIG_VAR)." ; \
> +		echo "Potential culprits:" ; \
> +		for p in $($(PKG)_DEPENDENT_OF) ; do echo " - $$p" ; done ; \

This does only work for first-level culprits.

For example, I added;
    BUSYBOX_DEPENDENCIES += exim

And I get:

    >>> berkeleydb 5.3.28 Patching libtool
    ERROR: A package must have added berkeleydb to its _DEPENDENCIES line but
    forgot to add the corresponding select / depends on BR2_PACKAGE_BERKELEYDB.
    Potential culprits:
    make[1]: *** [.../berkeleydb-5.3.28/.stamp_configured] Error 1
    make: *** [_all] Error 2

That's because the real culprit is not directly the cause of the
berkeleydb dependency; the depenency chain is two-or-more levels deep.

So, NAK on this patch (even though that was my idea originally, IIRC).

I'll (later!) to find a solution...

Regards,
Yann E. MORIN.

>  		exit 1 ; \
>  	fi
>  endif
> @@ -777,6 +779,12 @@ endif # ifneq ($$(call qstrip,$$($(2)_SOURCE)),)
>  # configuration
>  ifeq ($$($$($(2)_KCONFIG_VAR)),y)
>  
> +# Store reverse build-dependency information: we add the name of the
> +# current package to the <pkg>_DEPENDENT_OF variable of all packages
> +# the current package depends on.
> +$$(eval $$(foreach d,$$($(2)_FINAL_ALL_DEPENDENCIES),\
> +	$$(call UPPERCASE,$$(d))_DEPENDENT_OF += $(1)$$(sep)))
> +
>  # Ensure the calling package is the declared provider for all the virtual
>  # packages it claims to be an implementation of.
>  ifneq ($$($(2)_PROVIDES),)
> -- 
> 2.6.1
> 
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCHv5 1/2] pkg-generic: detect incorrectly used package

[Yann E. MORIN]

Thomas, All,

On 2015-10-09 11:15 +0200, Thomas Petazzoni spake thusly:
> In Buildroot, the selection of a package from a Config.in level and
> from a Makefile level are completely disconnected. This can lead to
> issues where the build of a package is triggered at the Makefile level
> due to the package being listed in another package <pkg>_DEPENDENCIES
> variable, even if that package is not enabled in the configuration.
> 
> This has for example been the case recently with python-can having
> 'python' in its <pkg>_DEPENDENCIES, while python-can could be enabled
> when Python 3.x is used, in which case the 'python' package should not
> be built.
> 
> To detect such issues more easily, this patch adds a check in the
> package infrastructure. When the build process of a package is being
> triggered, we verify that the package is enabled in the
> configuration. We do this check in the "configure" step, since this
> step is the first common step between the normal download case and the
> "local site method" / "package override" case.
> 
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
[--SNIP--]
> diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
> index 76ec295..a831199 100644
> --- a/package/pkg-generic.mk
> +++ b/package/pkg-generic.mk
> @@ -143,6 +143,16 @@ $(foreach dir,$(call qstrip,$(BR2_GLOBAL_PATCH_DIR)),\
>  
>  # Configure
>  $(BUILD_DIR)/%/.stamp_configured:
> +# Only trigger the check for default builds. If the user forces
> +# building a package, even if not enabled in the configuration, we
> +# want to accept it.
> +ifeq ($(MAKECMDGOALS),)
> +	@if test "$($(PKG)_TYPE)" = "target" -a -z "$($($(PKG)_KCONFIG_VAR))" ; then \
> +		echo "ERROR: A package must have added $($(PKG)_NAME) to its _DEPENDENCIES line but" ; \

As I reported in the second patch of this series, the package being
build might second-or-deeper in the dependency chain.

So, if we have the existing _correct_ dependencies:
  foo -> bar
  bar -> buz
  buz -> daz

and we then add an incorrect dependency;
  alpha -> foo

then the build order guranatees that daz is built first, and the we
report that something is incorrectly selecting daz, while the reall
issue is that something is incorrectly selecting foo.

So, we'd probably need to state something like:

    ERROR: $(1) is in the dependency chain of a package that has
    added it to is _DEPENDENCIES line (directly or indirectly)
    without selecting it from Config.in.

I'm not too happy with that phrasing, because it is still obscur for a
new-comer. But we would instantly recognise the pattern and it would be
relatively easy to spot the real culprit.

Thoughts?

Regards,
Yann E. MORIN.

> +		echo "forgot to add the corresponding select / depends on $($(PKG)_KCONFIG_VAR)." ; \
> +		exit 1 ; \
> +	fi
> +endif
>  	@$(call step_start,configure)
>  	@$(call MESSAGE,"Configuring")
>  	$(foreach hook,$($(PKG)_PRE_CONFIGURE_HOOKS),$(call $(hook))$(sep))
> -- 
> 2.6.1
> 
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCHv5 1/2] pkg-generic: detect incorrectly used package

[Thomas Petazzoni]

Hello,

On Fri,  9 Oct 2015 11:15:05 +0200, Thomas Petazzoni wrote:
> In Buildroot, the selection of a package from a Config.in level and
> from a Makefile level are completely disconnected. This can lead to
> issues where the build of a package is triggered at the Makefile level
> due to the package being listed in another package <pkg>_DEPENDENCIES
> variable, even if that package is not enabled in the configuration.
> 
> This has for example been the case recently with python-can having
> 'python' in its <pkg>_DEPENDENCIES, while python-can could be enabled
> when Python 3.x is used, in which case the 'python' package should not
> be built.
> 
> To detect such issues more easily, this patch adds a check in the
> package infrastructure. When the build process of a package is being
> triggered, we verify that the package is enabled in the
> configuration. We do this check in the "configure" step, since this
> step is the first common step between the normal download case and the
> "local site method" / "package override" case.
> 
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
> Changes since v4:
>  - Use $($(PKG)_KCONFIG_VAR) and $($(PKG)_TYPE) as suggested by Arnout.
>  - Split the "potential culprit" mechanism into a separate commit, as
>    suggested by Yann.

I've applied, after taking into account the comment from Yann (and
fixing a minor issue with it: $(1) cannot be used, it should have been
$($(PKG)_NAME)).

Thanks!

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com