Add -mno-crt0 to moxie port

From-SVN: r191629

ChangeLog

+2012-09-21  Anthony Green  <green@moxielogic.com>
+
+	* config/moxie/moxie.opt: Add -mno-crt0 option.
+	* config/moxie/moxie.h (STARTFILE_SPEC): Handle -mno-crt0 option.
+	* doc/invoke.texi (Option Summary): Document -mno-crt0 option.
+
 2012-09-20  Walter Lee  <walt@tilera.com>
 
 	* configure.ac: Add tilegx to list of targets that support gold.

gcc/config/moxie/moxie.h

 /* Target Definitions for moxie.
-   Copyright (C) 2008, 2009, 2010  Free Software Foundation, Inc.
+   Copyright (C) 2008, 2009, 2010, 2012  Free Software Foundation, Inc.
    Contributed by Anthony Green.
 
    This file is part of GCC.
@@ -22,7 +22,7 @@
 #define GCC_MOXIE_H
 
 #undef  STARTFILE_SPEC
-#define STARTFILE_SPEC "crt0%O%s crti.o%s crtbegin.o%s"
+#define STARTFILE_SPEC "%{!mno-crt0:crt0%O%s} crti.o%s crtbegin.o%s"
 
 /* Provide an ENDFILE_SPEC appropriate for svr4.  Here we tack on our own
    magical crtend.o file (see crtstuff.c) which provides part of the

gcc/config/moxie/moxie.opt

@@ -25,3 +25,7 @@ Generate big-endian code
 mel
 Target RejectNegative Report Mask(LITTLE_ENDIAN)
 Generate little-endian code
+
+; Ignored by the compiler
+mno-crt0
+Target RejectNegative

gcc/doc/invoke.texi

@@ -777,7 +777,7 @@ Objective-C and Objective-C++ Dialects}.
 -mno-crt0  -mrelax -mliw -msetlb}
 
 @emph{Moxie Options}
-@gccoptlist{-meb  -mel}
+@gccoptlist{-meb -mel -mno-crt0}
 
 @emph{PDP-11 Options}
 @gccoptlist{-mfpu  -msoft-float  -mac0  -mno-ac0  -m40  -m45  -m10 @gol
@@ -16476,6 +16476,10 @@ configurations.
 @opindex mel
 Generate little-endian code.
 
+@item -mno-crt0
+@opindex mno-crt0
+Do not link in the C run-time initialization object file.
+
 @end table
 
 @node PDP-11 Options