RE: Multiple rules for same target: what is the order of prerequisites in $^ and what does $< expand to?

[Cook, Malcolm]

>On Wed, 2023-09-27 at 16:50 +0200, Renaud Pacalet wrote:
>> Thanks for your answer, Bahman. Not sure what "equivalent" means but
>> with the following Makefile:
>> 
>> %.a: %.b
>> 
>> a.a: a.c
>>      echo $^
>
>The first pattern rule here does not define a pattern rule. It
>*cancels* a pattern rule. See:
>https://www.gnu.org/software/make/manual/html_node/Canceling-Rules.html
>
>It's not possible for two different pattern rules to both be in effect
>when building the same target, just like it's not possible for multiple
>implicit rules with recipes to be in effect.
>
>Basically, the way it works is that the prerequisites on the rule that
>has the recipe come first, and any other prerequisites added by rules
>without recipes are added afterwards, in the order in which they appear
>in the makefile.
>

Excellent!  

This answers a question I've wondered about in the past.  

Might this be included as part of [Multiple Rules for One 
Target](https://www.gnu.org/software/make/manual/make.html#Multiple-Rules) 
documentation?

~ Malcolm

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