[PATCH] Make: Fix if_changed when command contains backslashes

[PATCH] Make: Fix if_changed when command contains backslashes

[Sascha Hauer]

The call if_changed mechanism does not work when the command
contains backslashes. This basically is an issue with lzo
and bzip2 compressed kernels. The compressed binaries do not
contain the uncompressed image size, so these use size_append
to append the size. This results in backslashes in the executed
command. With this if_changed always detects a change in the
command and rebuilds the compressed image even if nothing
has changed.

Fix this by escaping backslashes in make-cmd

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 scripts/Kbuild.include |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 6a3ee98..afa4459 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -209,7 +209,7 @@ endif
 # >$< substitution to preserve $ when reloading .cmd file
 # note: when using inline perl scripts [perl -e '...$$t=1;...']
 # in $(cmd_xxx) double $$ your perl vars
-make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1)))))
+make-cmd = $(subst \\,\\\\,$(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1))))))
 
 # Find any prerequisites that is newer than target or that does not exist.
 # PHONY targets skipped in both cases.
-- 
1.7.10.4

Re: [PATCH] Make: Fix if_changed when command contains backslashes

[Sascha Hauer]

On Fri, Sep 07, 2012 at 11:35:52AM +0200, Sascha Hauer wrote:
> The call if_changed mechanism does not work when the command
> contains backslashes. This basically is an issue with lzo
> and bzip2 compressed kernels. The compressed binaries do not
> contain the uncompressed image size, so these use size_append
> to append the size. This results in backslashes in the executed
> command. With this if_changed always detects a change in the
> command and rebuilds the compressed image even if nothing
> has changed.
> 
> Fix this by escaping backslashes in make-cmd
> 
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

This was found and fixed together with Jan Lübbe, so I should not
forget his credits:

Signed-off-by: Jan Luebbe <jlu@pengutronix.de>

Sascha

> ---
>  scripts/Kbuild.include |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
> index 6a3ee98..afa4459 100644
> --- a/scripts/Kbuild.include
> +++ b/scripts/Kbuild.include
> @@ -209,7 +209,7 @@ endif
>  # >$< substitution to preserve $ when reloading .cmd file
>  # note: when using inline perl scripts [perl -e '...$$t=1;...']
>  # in $(cmd_xxx) double $$ your perl vars
> -make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1)))))
> +make-cmd = $(subst \\,\\\\,$(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1))))))
>  
>  # Find any prerequisites that is newer than target or that does not exist.
>  # PHONY targets skipped in both cases.
> -- 
> 1.7.10.4
> 
> 

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