4 files changed, 11 insertions, 13 deletions
diff --git a/source3/configure.in b/source3/configure.in
index 497c4ac624..8c728deea2 100644
--- a/source3/configure.in
+++ b/source3/configure.in
@@ -1337,19 +1337,6 @@ AC_CHECK_LIB(exc, trace_back_stack)
 # implicit declaration warnings without failing the test (in developer mode)
 ac_no_error_on_warning_CFLAGS="${CFLAGS}"
 
-# Since --enable-developer causes warnings to be treated as errors during
-# compilation, we should avoid using features that will fail to compile.
-#
-# We don't want to enable this earlier because the built-in functions such as
-# memset fail to configure properly.
-
-if test x"$samba_cv_HAVE_Werror_implicit_function_declaration" = x"yes" -a \
-        x"$developer" = xyes; then
-  CFLAGS="${CFLAGS} -Werror-implicit-function-declaration"
-  ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
-  ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
-fi
-
 echo -n "checking for GPFS GPL libs... "
 save_LIBS="$LIBS"
 LIBS="$LIBS -lgpfs_gpl"
diff --git a/source3/lib/replace/README b/source3/lib/replace/README
index 77558b2ca9..a2f9e2fa29 100644
--- a/source3/lib/replace/README
+++ b/source3/lib/replace/README
@@ -55,6 +55,11 @@ strtoull
 socketpair
 strptime
 
+These external declarations are provided for those systems which lack the
+declaration but provide the function:
+
+readahead
+
 Types:
 bool
 socklen_t
diff --git a/source3/lib/replace/libreplace.m4 b/source3/lib/replace/libreplace.m4
index e9b19b7cf5..a030ce2e90 100644
--- a/source3/lib/replace/libreplace.m4
+++ b/source3/lib/replace/libreplace.m4
@@ -155,6 +155,7 @@ AC_CHECK_FUNCS(pread pwrite strndup strcasestr strtok_r mkdtemp socketpair)
 AC_HAVE_DECL(setresuid, [#include <unistd.h>])
 AC_HAVE_DECL(setresgid, [#include <unistd.h>])
 AC_HAVE_DECL(errno, [#include <errno.h>])
+AC_HAVE_DECL(readahead, [#include <fcntl.h>])
 
 AC_CACHE_CHECK([for secure mkstemp],samba_cv_HAVE_SECURE_MKSTEMP,[
 AC_TRY_RUN([#include <stdlib.h>
diff --git a/source3/lib/replace/replace.h b/source3/lib/replace/replace.h
index b96356ac46..916d5a55e6 100644
--- a/source3/lib/replace/replace.h
+++ b/source3/lib/replace/replace.h
@@ -111,6 +111,11 @@ extern char *sys_errlist[];
 extern int errno;
 #endif
 
+#if defined(HAVE_LINUX_READAHEAD) && ! defined(HAVE_READAHEAD_DECL)
+ssize_t readahead(int fd, off64_t offset, size_t count);
+#endif
+
+
 #ifndef HAVE_STRDUP
 #define strdup rep_strdup
 char *rep_strdup(const char *s);