This patch creates a crypt-glibc subdirectory which builds the
libgcrypt files, but this time against the glibc sources.

The default subdirs list does not include this subdirectory because
the file names conflict with the crypt directory.  The spec file does
not use the install target to install the built libcrypt.so file,
either.

Index: b/crypt-glibc/Makefile
===================================================================
--- /dev/null
+++ b/crypt-glibc/Makefile
@@ -0,0 +1,61 @@
+# Build libcrypt against internal cryptographic algorithms.
+# Copyright (C) 1996-2016 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+#
+#	Sub-makefile for crypt() portion of the library.
+#
+subdir	:= crypt-glibc
+
+include ../Makeconfig
+
+extra-libs := libcrypt
+extra-libs-others := $(extra-libs)
+
+# Use the sources in the crypt subdirectory.
+vpath %.c ../crypt
+vpath %.input ../crypt
+
+libcrypt-routines := \
+  crypt-entry md5-crypt sha256-crypt sha512-crypt crypt crypt_util
+
+tests := cert md5c-test sha256c-test sha512c-test badsalttest
+
+libcrypt-routines += md5 sha256 sha512
+
+tests += md5test sha256test sha512test
+
+# The test md5test-giant uses up to 400 MB of RSS and runs on a fast
+# machine over a minute.
+xtests = md5test-giant
+
+include ../Rules
+
+md5-routines := md5 $(filter md5%,$(libcrypt-sysdep_routines))
+sha256-routines := sha256 $(filter sha256%,$(libcrypt-sysdep_routines))
+sha512-routines := sha512 $(filter sha512%,$(libcrypt-sysdep_routines))
+
+$(objpfx)md5test: $(patsubst %, $(objpfx)%.o,$(md5-routines))
+$(objpfx)md5test-giant: $(patsubst %, $(objpfx)%.o,$(md5-routines))
+$(objpfx)sha256test: $(patsubst %, $(objpfx)%.o,$(sha256-routines))
+$(objpfx)sha512test: $(patsubst %, $(objpfx)%.o,$(sha512-routines))
+
+ifeq (yes,$(build-shared))
+$(addprefix $(objpfx),$(tests)): $(objpfx)libcrypt.so
+else
+$(addprefix $(objpfx),$(tests)): $(objpfx)libcrypt.a
+endif
Index: b/crypt/md5.c
===================================================================
--- a/crypt/md5.c
+++ b/crypt/md5.c
@@ -270,4 +270,4 @@ md5_process_bytes (const void *buffer, s
     }
 }
 
-#include <md5-block.c>
+#include "md5-block.c"
Index: b/crypt/sha256.c
===================================================================
--- a/crypt/sha256.c
+++ b/crypt/sha256.c
@@ -211,4 +211,4 @@ __sha256_process_bytes (const void *buff
     }
 }
 
-#include <sha256-block.c>
+#include "sha256-block.c"
Index: b/crypt/sha512.c
===================================================================
--- a/crypt/sha512.c
+++ b/crypt/sha512.c
@@ -235,4 +235,4 @@ __sha512_process_bytes (const void *buff
     }
 }
 
-#include <sha512-block.c>
+#include "sha512-block.c"
Index: b/crypt-glibc/Versions
===================================================================
--- /dev/null
+++ b/crypt-glibc/Versions
@@ -0,0 +1,5 @@
+libcrypt {
+  GLIBC_2.0 {
+    crypt; crypt_r; encrypt; encrypt_r; fcrypt; setkey; setkey_r;
+  }
+}