diff --git a/lib/Makefile.in b/lib/Makefile.in
index a39102957..b3c7e6d28 100644
--- a/lib/Makefile.in
+++ b/lib/Makefile.in
@@ -3452,6 +3452,7 @@ string.h: string.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H
 	      -e 's|@''REPLACE_FFSLL''@|$(REPLACE_FFSLL)|g' \
 	      -e 's|@''REPLACE_MEMCHR''@|$(REPLACE_MEMCHR)|g' \
 	      -e 's|@''REPLACE_MEMMEM''@|$(REPLACE_MEMMEM)|g' \
+	      -e 's|@''REPLACE_FREE''@|$(REPLACE_FREE)|g' \
 	      -e 's|@''REPLACE_STPNCPY''@|$(REPLACE_STPNCPY)|g' \
 	      -e 's|@''REPLACE_STRCHRNUL''@|$(REPLACE_STRCHRNUL)|g' \
 	      -e 's|@''REPLACE_STRDUP''@|$(REPLACE_STRDUP)|g' \
@@ -3948,6 +3949,7 @@ wchar.h: wchar.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H)
 	  sed -e 's|@''REPLACE_MBSTATE_T''@|$(REPLACE_MBSTATE_T)|g' \
 	      -e 's|@''REPLACE_BTOWC''@|$(REPLACE_BTOWC)|g' \
 	      -e 's|@''REPLACE_WCTOB''@|$(REPLACE_WCTOB)|g' \
+	      -e 's|@''REPLACE_FREE''@|$(REPLACE_FREE)|g' \
 	      -e 's|@''REPLACE_MBSINIT''@|$(REPLACE_MBSINIT)|g' \
 	      -e 's|@''REPLACE_MBRTOWC''@|$(REPLACE_MBRTOWC)|g' \
 	      -e 's|@''REPLACE_MBRLEN''@|$(REPLACE_MBRLEN)|g' \
diff --git a/gnulib-tests/strerror_r.c b/gnulib-tests/strerror_r.c
index f0244520b..90043c223 100644
--- a/gnulib-tests/strerror_r.c
+++ b/gnulib-tests/strerror_r.c
@@ -34,33 +34,26 @@
 
 #include "strerror-override.h"
 
-#if (__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__) && HAVE___XPG_STRERROR_R /* glibc >= 2.3.4, cygwin >= 1.7.9 */
+#if STRERROR_R_CHAR_P
 
-# define USE_XPG_STRERROR_R 1
-extern
-#ifdef __cplusplus
-"C"
-#endif
-int __xpg_strerror_r (int errnum, char *buf, size_t buflen);
+# if HAVE___XPG_STRERROR_R
+_GL_EXTERN_C int __xpg_strerror_r (int errnum, char *buf, size_t buflen);
+# endif
 
-#elif HAVE_DECL_STRERROR_R && !(__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__)
+#elif HAVE_DECL_STRERROR_R
 
-/* The system's strerror_r function is OK, except that its third argument
+/* The system's strerror_r function's API is OK, except that its third argument
    is 'int', not 'size_t', or its return type is wrong.  */
 
 # include <limits.h>
 
-# define USE_SYSTEM_STRERROR_R 1
-
-#else /* (__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__ ? !HAVE___XPG_STRERROR_R : !HAVE_DECL_STRERROR_R) */
+#else
 
 /* Use the system's strerror().  Exclude glibc and cygwin because the
    system strerror_r has the wrong return type, and cygwin 1.7.9
    strerror_r clobbers strerror.  */
 # undef strerror
 
-# define USE_SYSTEM_STRERROR 1
-
 # if defined __NetBSD__ || defined __hpux || (defined _WIN32 && !defined __CYGWIN__) || defined __sgi || (defined __sun && !defined _LP64) || defined __CYGWIN__
 
 /* No locking needed.  */
@@ -166,22 +159,28 @@ strerror_r (int errnum, char *buf, size_t buflen)
     int ret;
     int saved_errno = errno;
 
-#if USE_XPG_STRERROR_R
+#if STRERROR_R_CHAR_P
 
     {
+      ret = 0;
+
+# if HAVE___XPG_STRERROR_R
       ret = __xpg_strerror_r (errnum, buf, buflen);
       if (ret < 0)
         ret = errno;
+# endif
+
       if (!*buf)
         {
           /* glibc 2.13 would not touch buf on err, so we have to fall
              back to GNU strerror_r which always returns a thread-safe
              untruncated string to (partially) copy into our buf.  */
-          safe_copy (buf, buflen, strerror_r (errnum, buf, buflen));
+          char *errstring = strerror_r (errnum, buf, buflen);
+          ret = errstring ? safe_copy (buf, buflen, errstring) : errno;
         }
     }
 
-#elif USE_SYSTEM_STRERROR_R
+#elif HAVE_DECL_STRERROR_R
 
     if (buflen > INT_MAX)
       buflen = INT_MAX;
@@ -245,7 +244,7 @@ strerror_r (int errnum, char *buf, size_t buflen)
       }
 # endif
 
-#else /* USE_SYSTEM_STRERROR */
+#else /* strerror_r is not declared.  */
 
     /* Try to do what strerror (errnum) does, but without clobbering the
        buffer used by strerror().  */
diff --git a/lib/string.in.h b/lib/string.in.h
index fa2e40c25..8977153c8 100644
--- a/lib/string.in.h
+++ b/lib/string.in.h
@@ -47,9 +47,6 @@
 /* NetBSD 5.0 mis-defines NULL.  */
 #include <stddef.h>
 
-/* Get free().  */
-#include <stdlib.h>
-
 /* MirBSD defines mbslen as a macro.  */
 #if @GNULIB_MBSLEN@ && defined __MirBSD__
 # include <wchar.h>
@@ -86,6 +83,13 @@
 
 /* The definition of _GL_WARN_ON_USE is copied here.  */
 
+/* Declare 'free' if needed for _GL_ATTRIBUTE_DEALLOC_FREE.  */
+#if (@REPLACE_FREE@ && !defined free \
+     && !(defined __cplusplus && defined GNULIB_NAMESPACE))
+_GL_EXTERN_C void free (void *);
+# define free rpl_free
+#endif
+_GL_EXTERN_C void free (void *);
 
 /* Clear a block of memory.  The compiler will not delete a call to
    this function, even if the block is dead after the call.  */
diff --git a/lib/wchar.in.h b/lib/wchar.in.h
index be5d36c8d..acb9d4ea6 100644
--- a/lib/wchar.in.h
+++ b/lib/wchar.in.h
@@ -72,9 +72,6 @@
 # include <stddef.h>
 #endif
 
-/* Get free().  */
-#include <stdlib.h>
-
 /* Include the original <wchar.h> if it exists.
    Some builds of uClibc lack it.  */
 /* The include_next requires a split double-inclusion guard.  */
@@ -149,6 +146,13 @@ typedef int rpl_mbstate_t;
 # endif
 #endif
 
+/* Declare 'free' if needed for _GL_ATTRIBUTE_DEALLOC_FREE.  */
+#if (@REPLACE_FREE@ && !defined free \
+     && !(defined __cplusplus && defined GNULIB_NAMESPACE))
+_GL_EXTERN_C void free (void *);
+# define free rpl_free
+#endif
+_GL_EXTERN_C void free (void *);
 
 /* Convert a single-byte character to a wide character.  */
 #if @GNULIB_BTOWC@