Re: [PATCH] Makefile: add and use the ".DELETE_ON_ERROR" flag

From: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
To: Felipe Contreras <felipe.contreras@gmail.com>
Cc: git@vger.kernel.org, Junio C Hamano <gitster@pobox.com>,
	Jeff King <peff@peff.net>
Subject: Re: [PATCH] Makefile: add and use the ".DELETE_ON_ERROR" flag
Date: Wed, 23 Jun 2021 21:59:16 +0200	[thread overview]
Message-ID: <87o8bw1hc5.fsf@evledraar.gmail.com> (raw)
In-Reply-To: <60d389d015943_4290208ae@natae.notmuch>

On Wed, Jun 23 2021, Felipe Contreras wrote:

> Ævar Arnfjörð Bjarmason wrote:
>> @@ -2243,7 +2253,6 @@ SCRIPT_DEFINES = $(SHELL_PATH_SQ):$(DIFF_SQ):$(GIT_VERSION):\
>>  	$(gitwebdir_SQ):$(PERL_PATH_SQ):$(SANE_TEXT_GREP):$(PAGER_ENV):\
>>  	$(perllibdir_SQ)
>>  define cmd_munge_script
>> -$(RM) $@ $@+ && \
>>  sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
>>      -e 's|@SHELL_PATH@|$(SHELL_PATH_SQ)|' \
>>      -e 's|@@DIFF@@|$(DIFF_SQ)|' \
>
> Any reason why the same isn't done for the $(BUILT_INS) target?
>
>> @@ -2514,7 +2522,6 @@ endif
>>  ifeq ($(GENERATE_COMPILATION_DATABASE),yes)
>>  all:: compile_commands.json
>>  compile_commands.json:
>> -	@$(RM) $@
>>  	$(QUIET_GEN)sed -e '1s/^/[/' -e '$$s/,$$/]/' $(compdb_dir)/*.o.json > $@+
>>  	@if test -s $@+; then mv $@+ $@; else $(RM) $@+; fi
>>  endif
>
> What about these?
>
>   $(REMOTE_CURL_ALIASES):

Uses a chain of ln/ln -s/cp, would need to add "-f" flags.

I've got another series I'm planning to (re-)submit to fix those ln/ln
-s/cp patterns.

>   $(LIB_FILE):

Can we rely on $(AR) happily clobbering things everywhere? Not knowing
is why I skipped it.

>   $(XDIFF_LIB): 

ditto.

>   $(ETAGS_TARGET):
>   tags:
>   cscope:

Addressed in the related:
https://lore.kernel.org/git/YNH+zsXDnRsT3uvZ@nand.local/T/#t

But yeah, the implicit point of "note that in the commit message" is
taken.