+If you want to add to, not replace, compile flags, you can use OURDEFS:
+ ./configure OURDEFS='-Wextra -Wno-sign-compare'
+
+---------------------------------
+Using a different build directory
+---------------------------------
+You can compile mmh in a different directory from the one containing
+the source code. Doing so allows you to compile it on more than one
+architecture at the same time. To do this, you must use a version of
+"make" that supports the "VPATH" variable, such as GNU "make". Change
+to the directory where you want the object files and executables to go
+and run the "configure" script. "configure" automatically checks for
+the source code in the directory that "configure" is in. For example,
+
+ cd /usr/local/src/mmh # source directory
+ make clean
+ cd /usr/local/solaris/mmh # build directory
+ /usr/local/src/mmh/configure
+ make
+