[m-rev.] diff: fix bug #379: warnings about deprecated feature macros with glibc 2.20

[Julien Fischer]

Does anyone know why we need the C files generated by mkinit to define 
_BSD_SOURCE?

--------------------------

Branches: 14.01, master

Fix bug #379: warnings about deprecated feature macros with glibc 2.20.

glibc version 2.20 will emit a warning if the macros _BSD_SOURCE or
_SVID_SOURCE are defined.  (They have been deprecated in favour of the macro
_DEFAULT_SOURCE).  The C files generated by mkinit define _BSD_SOURCE,
consequently causing a warning to be emitted by the preprocessor every time you
build an executable on systems with the affected version of glibc.

Also defining _DEFAULT_SOURCE will disable the warning.

util/mkinit.c:
 	Define _DEFAULT_SOURCE in order to suppress the warning described
         above.

diff --git a/util/mkinit.c b/util/mkinit.c
index 0309215..92a21c2 100644
--- a/util/mkinit.c
+++ b/util/mkinit.c
@@ -318,8 +318,15 @@ static const char header1[] =
      "**\n"
      ;

+/*
+** NOTE: _DEFAULT_SOURCE is defined in order to suppress a warning
+** about _BSD_SOURCE being deprecated in glibc 2.20.  We keep the
+** definition of the deprecated macro about for compatibility with
+** older versions of glibc.
+*/
  static const char header2[] =
      "*/\n"
+    "#define _DEFAULT_SOURCE\n"
      "#define _BSD_SOURCE\n"
      "#include <stddef.h>\n"
      "#ifdef MR_PROFILE_SBRK\n"