Review for 7141244: build-infra merge: Include $(SPEC) in makefiles and make variables overridable

[Erik Joelsson]

http://cr.openjdk.java.net/~erikj/7141244/webrev.00/ 
<http://cr.openjdk.java.net/%7Eerikj/7141244/webrev.00/>
178 lines changed: 115 ins; 7 del; 56 mod; 4625 unchg

7141244: build-infra merge: Include $(SPEC) in makefiles and make 
variables overridable

The build-infra project is starting to move into jdk8. For the hotspot 
build to stay compatible with the changes, key hotspot makefiles need to 
add an optional include statement:


-include $(SPEC)

In the new build system, the spec file is generated by configure and 
contains the configuration for the build. Only a handfull of files need 
to add this line.

In addition to including the spec file, some variables need to be 
changed to only be set conditionally so that a value from the spec file 
takes precedence. These are: CC, CXX, CPP, AS, MCS, STRIP, NM, NAWK (and 
for windows RC and MT). The hotspot makefiles should check each variable 
if it's already set or if it has a gnumake default value.

These changes have been verified to work for hotspot-rt. Jdk7u will be 
verified as well before pushing.

/Erik