Checking if your kit is complete... Looks good Writing Makefile for Win32::API::OutputDebugString cp OutputDebugString.pm blib/lib/Win32/API/OutputDebugString.pm AutoSplitting blib/lib/Win32/API/OutputDebugString.pm (blib/lib/auto/Win32/API/OutputDebugString) /Users/cpanrun/build/5.10.0/bin/perl /Users/cpanrun/build/5.10.0/lib/ExtUtils/xsubpp -typemap /Users/cpanrun/build/5.10.0/lib/ExtUtils/typemap OutputDebugString.xs > OutputDebugString.xsc && mv OutputDebugString.xsc OutputDebugString.c Please specify prototyping behavior for OutputDebugString.xs (see perlxs manual) gcc -c -fno-common -DPERL_DARWIN -no-cpp-precomp -arch ppc -arch i386 -nostdinc -B/Developer/SDKs/MacOSX10.4u.sdk/usr/include/gcc -B/Developer/SDKs/MacOSX10.4u.sdk/usr/lib/gcc -isystem/Developer/SDKs/MacOSX10.4u.sdk/usr/include -F/Developer/SDKs/MacOSX10.4u.sdk/System/Library/Frameworks -mmacosx-version-min=10.3 -DPRIVLIB_LAST_IN_INC -fno-strict-aliasing -pipe -O3 -DVERSION=\"0.03\" -DXS_VERSION=\"0.03\" "-I/Users/cpanrun/build/5.10.0/lib/CORE" OutputDebugString.c OutputDebugString.xs:5:21: error: windows.h: No such file or directory OutputDebugString.xs:5:21: error: windows.h: No such file or directory lipo: can't open input file: /var/tmp//cc15bQXX.out (No such file or directory) make: *** [OutputDebugString.o] Error 1