Index: Makefile.PL
--- Makefile.PL.orig
+++ Makefile.PL
@@ -49,9 +49,9 @@ WriteMakefile
                            },
 
    'LICENSE'            => 'perl_5',
-   'LIBS'               => ['-lgmp'],   # e.g., '-lm'
+   'LIBS'               => ["$ENV{LDFLAGS} -lgmp"],   # e.g., '-lm'
    'DEFINE'             => '',          # e.g., '-DHAVE_SOMETHING'
-   'INC'                => '',          # e.g., '-I/usr/include/other'
+   'INC'                => "$ENV{CPPFLAGS}",          # e.g., '-I/usr/include/other'
    'SIGN'               => 1,
 
    'META_MERGE'         => {