Best way to do conditionals ?

[David Holmes]

On 12/04/2013 11:39 PM, David Chase wrote:
> Sanity check -- this is make 3.81, right?

Right.

> I checked on both MacOS 10.8 and Ubuntu
> Because (as is always the case) "it works for me":

Thanks for the sanity check.

This implies to me that either

a) it is a phase 1 versus phase 2 issue, but given the content of 
spec.gmk I can't see how that can be the case; or

b) the value of something is not what I naively thing it is ...

but I have investigated both of those in depth and nothing seems to be 
wrong. Yet I always take the else path :(

This is driving me nuts!

David
-----

> --------------
> JVM_VARIANT_SERVER := true
> JVM_VARIANT_CLIENT := true
> CLIENT_AND_SERVER1 := $(and $(findstring true, $(JVM_VARIANT_SERVER)), $(findstring true, $(JVM_VARIANT_CLIENT)))
> CLIENT_AND_SERVER2 := $(and $(JVM_VARIANT_SERVER),  $(JVM_VARIANT_CLIENT))
>
> ifeq ($(CLIENT_AND_SERVER1), true)
> one: two
> 	@echo one then C=$(JVM_VARIANT_CLIENT) S=$(JVM_VARIANT_SERVER) BOTH1=$(CLIENT_AND_SERVER1) BOTH2=$(CLIENT_AND_SERVER2)
> else
> one: two
> 	@echo one else C=$(JVM_VARIANT_CLIENT) S=$(JVM_VARIANT_SERVER) BOTH1=$(CLIENT_AND_SERVER1) BOTH2=$(CLIENT_AND_SERVER2)
> endif
>
> ifeq ($(CLIENT_AND_SERVER2), true)
> two:
> 	@echo two then C=$(JVM_VARIANT_CLIENT) S=$(JVM_VARIANT_SERVER) BOTH1=$(CLIENT_AND_SERVER1) BOTH2=$(CLIENT_AND_SERVER2)
> else
> two:
> 	@echo two else C=$(JVM_VARIANT_CLIENT) S=$(JVM_VARIANT_SERVER) BOTH1=$(CLIENT_AND_SERVER1) BOTH2=$(CLIENT_AND_SERVER2)
> endif
> -----------------
> "make one" yields
>
> two then C=true S=true BOTH1=true BOTH2=true
> one then C=true S=true BOTH1=true BOTH2=true
>
> I experimented with string "true" instead of true and with "   true   "
> and got the expected results (findstring true, as-boolean false).
> So what's different about our glorious Makefiles?
> Is it possibly indentation-related?  No, only if the indent is a tab, and then it gets noisy:
>
> make
> Makefile:11: warning: overriding commands for target `one'
> Makefile:8: warning: ignoring old commands for target `one'
> two then C=true S=true BOTH1=true BOTH2=true
> one else C=true S=true BOTH1=true BOTH2=true
>
> David
>
> On 2013-04-12, at 8:33 AM, David Holmes <david.holmes at oracle.com> wrote:
>
>> On 12/04/2013 7:02 PM, David Holmes wrote:
>>> I need to examine the JVM_VARIANT(S) variables and logically I want to do:
>>>
>>> if (client and server)
>>>    ...
>>> else
>>>    ...
>>> endif
>>>
>>>
>>> Nesting if blocks doesn't work - I need a conjunction, or a way to
>>> define a single variable using a conjunction.
>>>
>>> Suggestions?
>>
>> So I re-discovered the "and" operation
>>
>>   CLIENT_AND_SERVER := $(and $(findstring true, $(JVM_VARIANT_SERVER)), $(findstring true, $(JVM_VARIANT_CLIENT)))
>>   ifeq ($(CLIENT_AND_SERVER), true)
>>     # Use the committed jvm.cfg for this 32 bit setup but add
>>     # minimal if needed
>>     $(JVMCFG): $(JVMCFG_SRC)
>>         $(call install-file)
>>         ifeq ($(JVM_VARIANT_MINIMAL1), true)
>>           $(PRINTF) "-minimal KNOWN\n">>$(@)
>>         endif
>>   else
>>     $(JVMCFG):
>>         @$(ECHO) C=$(JVM_VARIANT_CLIENT) S=$(JVM_VARIANT_SERVER) BOTH=$(CLIENT_AND_SERVER)
>>
>> Yet I always execute the else but print:
>>
>> C=true S=true BOTH=true
>>
>>
>> I'm stumped! :(
>>
>> Thanks,
>> David
>