Mark '--with-isa-spec' option out of date.

Author: pz9115

README.md

@@ -149,16 +149,10 @@ GDB_TARGET_FLAGS_EXTRA, GLIBC_TARGET_FLAGS_EXTRA, NEWLIB_TARGET_FLAGS_EXTRA,
 LLVM_EXTRA_CONFIGURE_FLAGS, QEMU_EXTRA_CONFIGURE_FLAGS```.
 Example: ```GCC_EXTRA_CONFIGURE_FLAGS=--with-gmp=/opt/gmp make linux```
 
-#### Set default ISA spec version
+#### Set default ISA spec version. (Out of date)
 
-`--with-isa-spec=` can specify the default version of the RISC-V Unprivileged
-(formerly User-Level) ISA specification.
-
-Possible options are: `2.2`, `20190608` and `20191213`.
-
-The default version is `20191213`.
-
-More details about this option you can refer this post [RISC-V GNU toolchain bumping default ISA spec to 20191213](https://groups.google.com/a/groups.riscv.org/g/sw-dev/c/aE1ZeHHCYf4).
+Warning! This option is out of date. Possible options are: `2.2`, `20190608`
+and `20191213`.
 
 #### Build with customized multi-lib configure.
 

configure

@@ -1406,7 +1406,7 @@ Optional Packages:
   --with-abi=lp64d        Sets the base RISC-V ABI, defaults to lp64d
   --with-tune=generic     Set the base RISC-V CPU, defaults to GCC's default
   --with-isa-spec=20191213
-                          Set the default ISA spec version, default to
+                          Warning! This option is out of date. Default to
                           20191213, available options: 2.2, 20190608, 20191213
   --with-sim=qemu         Sets the base RISC-V Simulator, defaults to qemu
   --with-languages=       Sets the enabled languages for GNU toolchain,

configure.ac

@@ -91,7 +91,7 @@ AS_IF([test "x$with_tune" != xno],
 
 AC_ARG_WITH(isa-spec,
 	[AS_HELP_STRING([--with-isa-spec=20191213],
-		[Set the default ISA spec version, default to 20191213, available options: 2.2, 20190608, 20191213])],
+		[Warning! This option is out of date. Default to 20191213, available options: 2.2, 20190608, 20191213])],
 	[],
 	[with_isa_spec=20191213]
 	)