invoke.texi (MIPS Options): Document -mno-float.

2012-07-30  Sandra Loosemore  <sandra@codesourcery.com>
	    Julian Brown  <julian@codesourcery.com>

	gcc/
	* doc/invoke.texi (MIPS Options): Document -mno-float.
	* config/mips/mips.h (MIPS_ARCH_FLOAT_SPEC): Make it know
	about -mno-float.

Co-Authored-By: Julian Brown <julian@codesourcery.com>

From-SVN: r189989

gcc/ChangeLog

+2012-07-30  Sandra Loosemore  <sandra@codesourcery.com>
+	    Julian Brown  <julian@codesourcery.com>
+
+	* doc/invoke.texi (MIPS Options): Document -mno-float.
+	* config/mips/mips.h (MIPS_ARCH_FLOAT_SPEC): Make it know
+	about -mno-float.
+
 2012-07-30  Joseph Myers  <joseph@codesourcery.com>
 
 	* doc/sourcebuild.texi (Subdirectories): Document common

gcc/config/mips/mips.h

@@ -713,7 +713,7 @@ struct mips_cpu_info {
    link-compatible.  */
 
 #define MIPS_ARCH_FLOAT_SPEC \
-  "%{mhard-float|msoft-float|march=mips*:; \
+  "%{mhard-float|msoft-float|mno-float|march=mips*:; \
      march=vr41*|march=m4k|march=4k*|march=24kc|march=24kec \
      |march=34kc|march=74kc|march=1004kc|march=5kc \
      |march=octeon|march=xlr: -msoft-float;		  \

gcc/doc/invoke.texi

@@ -733,7 +733,8 @@ Objective-C and Objective-C++ Dialects}.
 -mabi=@var{abi}  -mabicalls  -mno-abicalls @gol
 -mshared  -mno-shared  -mplt  -mno-plt  -mxgot  -mno-xgot @gol
 -mgp32  -mgp64  -mfp32  -mfp64  -mhard-float  -msoft-float @gol
--msingle-float  -mdouble-float  -mdsp  -mno-dsp  -mdspr2  -mno-dspr2 @gol
+-mno-float -msingle-float  -mdouble-float  @gol
+-mdsp  -mno-dsp  -mdspr2  -mno-dspr2 @gol
 -mmcu -mmno-mcu @gol
 -mfpu=@var{fpu-type} @gol
 -msmartmips  -mno-smartmips @gol
@@ -15633,6 +15634,18 @@ Use floating-point coprocessor instructions.
 Do not use floating-point coprocessor instructions.  Implement
 floating-point calculations using library calls instead.
 
+@item -mno-float
+@opindex mno-float
+Equivalent to @option{-msoft-float}, but additionally asserts that the
+program being compiled does not perform any floating-point operations.
+This option is presently supported only by some bare-metal MIPS
+configurations, where it may select a special set of libraries
+that lack all floating-point support (including, for example, the
+floating-point @code{printf} formats).  
+If code compiled with @code{-mno-float} accidentally contains
+floating-point operations, it is likely to suffer a link-time
+or run-time failure.
+
 @item -msingle-float
 @opindex msingle-float
 Assume that the floating-point coprocessor only supports single-precision