>
>>Thoughts? Comments? 
>
>>+.if !defined(_SRC_TOP_)
>>+# Find Makefile.build
>>+_SRC_TOP_!=    MF="${.CURDIR}"; \
>>+               while `/usr/bin/true`; \
>>+               do \
>>+                       echo $${MF} >&2;  \
>>+                       if [ -f "$${MF}/Makefile.build" ]; then \
>>+                               echo "$${MF}/"; \
>>+                               break; \
>>+                       fi; \
>>+                       dir1=`cd $${MF}; pwd`; \
>>+                       dir2=`cd $${MF}/..; pwd`; \
>>+                       if [ "$$dir1" = "$$dir2" ]; then \
>>+                               echo ""; \
>>+                               break; \
>>+                       else \
>>+                               MF="$${MF}/.."; \
>>+                       fi; \
>>+               done
>
>This is more complex than necessary.  "while :" is all you need 
>for an infinite loop btw.  Anyway, either simply use `dirname` on 
>your current guess or my preference:
>
>_SRC_TOP_!= cd ${.CURDIR}; while :; do \
>	    here=`pwd`; \
>	    [ -f Makefile.build  ] && { echo $$here; break; }; \
>	    case $$here in /) break;; esac; \
>	    cd ..; \
>	done 

I knew this could be made smaller. I wasn't worried about the shell code so
much as getting it working. I knew it could be smaller.


>
>>+MAKE+= _SRC_TOP_=${_SRC_TOP_:Q}
>
>Also I'm not at all keen on appending to MAKE.
>Use .MAKEFLAGS or 

Doesn't work. MAKEFLAGS gets passed in, but doesn't get evaluated so it's
pointless. Check the source, only $MAKE gets re-evaluated on a new make.
Line 721 or so of main.c in usr.bin/make

>.MAKEOVERRIDES+= _SRC_TOP_
>will do the trick.

Didn't try that. $MAKE works and reading the source MAKEOVERRIDES doesn't
get evaluated either.

James