>>> Unpacking source...
>>> Unpacking coq-8.1pl1.tar.gz to /var/tmp/portage/sci-mathematics/coq-8.1_p1/work
>>> Source unpacked.
>>> Compiling source in /var/tmp/portage/sci-mathematics/coq-8.1_p1/work/coq-8.1pl1 ...
Unknown option "opt".
Available options for configure are:

-help
	Displays this help page

-prefix <dir>
	Set installation directory to <dir>

-local
	Set installation directory to the current source tree

-src
	Specifies the source directory

-bindir
-libdir
-mandir
	Specifies where to install bin/lib/man files resp.

-emacslib
-emacs
	Specifies where emacs files are to be installed

-coqdocdir
	Specifies where Coqdoc style files are to be installed

-camldir
	Tells configure where to look for OCaml files

-arch
	Specifies the architecture

-opt
	Specifies whether or not to generate optimized executables

-fsets (all|basic)
-reals (all|basic)
Specifies whether or not to compile full FSets/Reals library

-coqide (opt|byte|no)
	Specifies whether or not to compile Coqide

-with-geoproof (yes|no)
	Specifies whether or not to use Geoproof binding

-with-cc <file>
-with-ar <file>
-with-ranlib <file>
	Tells configure where to find gcc/ar/ranlib executables

-byte-only
	Compiles only bytecode version of Coq

-debug
	Add debugging information in the Coq executables

-profile
	Add profiling information in the Coq executables

-annotate
	Compiles Coq with -dtypes option
 * 
 * ERROR: sci-mathematics/coq-8.1_p1 failed.
 * Call stack:
 *   ebuild.sh, line 1654:   Called dyn_compile
 *   ebuild.sh, line 990:   Called qa_call 'src_compile'
 *   ebuild.sh, line 44:   Called src_compile
 *   coq-8.1_p1.ebuild, line 45:   Called die
 * 
 * configure failed
 * If you need support, post the topmost build error, and the call stack if relevant.
 * A complete build log is located at '/var/tmp/portage/sci-mathematics/coq-8.1_p1/temp/build.log'.
 *