title: Help with installing ECL (Embeddable Common Lisp) via mingw32 or mingw-64 on Win7-64
body: <p>I'm trying to compile <a href="http://sourceforge.net/projects/ecls/files/ecls/10.4/ecl-10.4.1.tar.gz/download" rel="nofollow">ECL 10.4.1</a> on my Win7 64-bit box, but am having issues.</p>
  
  <p>I've attempted the build with both <a href="http://sourceforge.net/projects/mingw/files/Automated%20MinGW%20Installer/mingw-get-inst/mingw-get-inst-20100909/mingw-get-inst-20100909.exe/download" rel="nofollow">mingw32/MSYS</a> and <a href="http://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Personal%20Builds/sezero_4.5_20101002/mingw-w64-bin_x86_64-mingw_20101002_4.5_sezero.zip/download" rel="nofollow">mingw-w64</a>/<a href="http://sourceforge.net/projects/mingw-w64/files/External%20binary%20packages%20%28Win64%20hosted%29/MSYS%20%2832-bit%29/MSYS-20100911.zip/download" rel="nofollow">MSYS</a>, using the exact packages linked to here.  Both have failed.</p>
  
  <p>With mingw32: ./configure passes, make fails as follows:</p>
  
  <pre><code>gcc -DECLDIR="\"/usr/local/lib/ecl-10.4.1\"" -I. -Ic:/my_home/ecl-10.4.1/build -I/c/my_home/ecl-10.4.1/src/c -I../ecl/gc -DECL_API -DECL_NO_LEGACY   -g -O2   -Dmingw32 -c -o main.o tmp.c
  
  In file included from c:/my_home/ecl-10.4.1/src/c/main.d:20:0:
  c:/my_home/ecl-10.4.1/build/ecl/ecl.h:71:4: error: #error "The Windows ports cannot be built without threads."
  make[2]: *** [main.o] Error 1
  make[2]: Leaving directory `/c/my_home/ecl-10.4.1/build/c'
  make[1]: *** [libeclmin.a] Error 2
  make[1]: Leaving directory `/c/my_home/ecl-10.4.1/build'
  make: *** [all] Error 2
  </code></pre>
  
  <p>With mingw-w64: ./configure fails as follows:</p>
  
  <pre><code>[...]
  checking for inttypes.h... yes
  checking for stdint.h... yes
  checking for unistd.h... yes
  checking gmp.h usability... no
  checking gmp.h presence... no
  checking for gmp.h... no
  checking gmp/gmp.h usability... no
  checking gmp/gmp.h presence... no
  checking for gmp/gmp.h... no
  configure: error: Can not find GMP header.
  </code></pre>
  
  <p>Does anyone have any advice for either of these?  Or is there another build system I could try?  (Other than Cygwin which I'm avoiding for licensing reasons.)</p>
  
  <hr>