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Writing Makefile for Tree::M

***
*** This module is written in C++, which is nontrivial to integrate into
*** most pre-built perls. If problems occur during compiling then edit (hack)
***
*** Makefile.PL
*** GiST/Makefile MT/Makefile
***
*** in this order. Especially wautch out for compile and optimization flags.
*** Have fun ;->
***

cp M.pm blib/lib/Tree/M.pm
cd GiST && make OPTIMIZE="-O6 -funroll-all-loops" CXX="g++" LD="g++" libGiST.a
make[1]: Entering directory `/export/home/cpanrun/depot/main/contrib-patched/perl/CPAN/src/Tree-M/GiST'
g++ -fpic -c  -O6 -funroll-all-loops -DUNIX  GiSTnode.cpp
g++ -fpic -c  -O6 -funroll-all-loops -DUNIX  GiST.cpp
g++ -fpic -c  -O6 -funroll-all-loops -DUNIX  GiSTfile.cpp
g++ -fpic -c  -O6 -funroll-all-loops -DUNIX  GiSTpredicate.cpp
g++ -fpic -c  -O6 -funroll-all-loops -DUNIX  GiSTcursor.cpp
rm -f libGiST.a
ar r libGiST.a GiSTnode.o GiST.o GiSTfile.o GiSTpredicate.o GiSTcursor.o
make[1]: ar: Command not found
make[1]: *** [libGiST.a] Error 127
make[1]: Leaving directory `/export/home/cpanrun/depot/main/contrib-patched/perl/CPAN/src/Tree-M/GiST'
make: *** [GiST/libGiST.a] Error 2