Best way to do conditionals ?

[David Chase]

Sanity check -- this is make 3.81, right?
I checked on both MacOS 10.8 and Ubuntu 
Because (as is always the case) "it works for me":
--------------
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