Enable option to prefer mini-gmp over libgmp

* configure.ac: rework gmp library detection. Add new flag.
* libguile.h: modify gmp header inclusion
* libguile/Makefile.am: add mini-gmp.[ch] files
* libguile/bytevectors.c: add mini-gmp headers
* libguile/gen-scmconfig.c: new #include variable GUILE_MINI_GMP
* libguile/init.c: add mini-gmp header
* libguile/mini-gmp.c: new file
* libguile/mini-gmp.h: new file
* libguile/numbers.c: add fallback for missing mpz_get_d_2exp
* libguile/numbers.h: yse mini-gmp header
* libguile/random.c: use mini-gmp header
* libguile/socket.c: use mini-gmp header

1 files changed, 7 insertions, 2 deletions

diff --git a/libguile/gen-scmconfig.c b/libguile/gen-scmconfig.c
index a3c732039..af6d0fe92 100644
--- a/libguile/gen-scmconfig.c
+++ b/libguile/gen-scmconfig.c
@@ -1,4 +1,4 @@
-/* Copyright 2003-2013,2018,2020
+/* Copyright 2003-2013,2018,2020,2021
      Free Software Foundation, Inc.
 
    This file is part of Guile.
@@ -206,7 +206,6 @@ main (int argc, char *argv[])
   pf ("#define SCM_HAVE_WINSOCK2_H 0 /* 0 or 1 */\n");
 #endif
 
-
   /*** GUILE_DEBUG (defined or undefined) ***/
   pf ("\n");
   pf ("/* Define to include various undocumented debugging functions. */\n");
@@ -378,6 +377,12 @@ main (int argc, char *argv[])
   pf ("/* Define to 1 if there is an auxiliary stack, as in ia64.  */\n");
   pf ("#define SCM_HAVE_AUXILIARY_STACK %d\n", SCM_I_GSC_HAVE_AUXILIARY_STACK);
 
+#ifdef GUILE_MINI_GMP
+  pf ("#define GUILE_MINI_GMP 1\n");
+#else
+  pf ("#undef GUILE_MINI_GMP\n");
+#endif
+
   printf ("#endif\n");
 
   return 0;