Build: Bump all toolchains to GCC 4.9.4 + Binutils 2.26.1

GCC 4.9.4 was already used for MIPS and all hosted targets; this enables
it across the board for everything (ie m68k and arm native)

Other changes:

 * Use '-Os' as the default optiomization for all targets
   (was only disabled for arm native)
 * Enable -funit-at-a-time and -Wextra
 * Drop all obsolete toolchain patches
 * Update ARM multilib/exception patch
 * Bump toolchain libs (gmp, mpfr, mpc) to recommended versions, and
   add 'isl' to enable better optimization & vectorization opportunities.

   (Will revisit optimization for the codecs and plugins at a later date)

Confirmed working:

 * armv4t     (ipodmini2g and many other PP502x targets)
 * arm >= v5  (sansaclipplus, ipod6g, ipodnano2g, sansafuzeplus)
 * m68k (ihp100)

Change-Id: If9ed405ae0f289d9adea46d4cf46bfefc2f4250d

1 files changed, 56 insertions, 0 deletions

diff --git a/tools/toolchain-patches/rockbox-multilibs-noexceptions-arm-elf-eabi-gcc-4.9.4.diff b/tools/toolchain-patches/rockbox-multilibs-noexceptions-arm-elf-eabi-gcc-4.9.4.diff
new file mode 100644
index 0000000000..cd98d3751c
--- /dev/null
+++ b/tools/toolchain-patches/rockbox-multilibs-noexceptions-arm-elf-eabi-gcc-4.9.4.diff
@@ -0,0 +1,56 @@
+diff -Naur gcc-4.9.4/gcc/config/arm/t-arm-elf gcc-4.9.4-fixed/gcc/config/arm/t-arm-elf
+--- gcc-4.9.4/gcc/config/arm/t-arm-elf  2014-01-02 17:23:26.000000000 -0500
++++ gcc-4.9.4-fixed/gcc/config/arm/t-arm-elf    2020-07-01 22:11:01.198403110 -0400
+@@ -44,6 +44,11 @@
+ #MULTILIB_EXCEPTIONS    += *mcpu=fa526/*mfloat-abi=hard*
+ #MULTILIB_EXCEPTIONS    += *mcpu=fa626/*mfloat-abi=hard*
+ 
++# We build a lib for each specific CPU Rockbox targets.  If anyone knows a better
++# way to do this, please let us know.
++MULTILIB_OPTIONS    += mcpu=arm7tdmi/mcpu=arm9tdmi/mcpu=arm9e/mcpu=arm926ej-s/mcpu=arm1136jf-s
++MULTILIB_DIRNAMES   += arm7tdmi arm9tdmi arm9e arm926ej-s arm1136jf-s
++
+ # MULTILIB_OPTIONS    += mcpu=ep9312
+ # MULTILIB_DIRNAMES   += ep9312
+ # MULTILIB_EXCEPTIONS += *mthumb/*mcpu=ep9312*
+@@ -56,8 +61,8 @@
+ # MULTILIB_DIRNAMES   += fpu soft
+ # MULTILIB_EXCEPTIONS += *mthumb/*mfloat-abi=hard*
+ # 
+-# MULTILIB_OPTIONS    += mno-thumb-interwork/mthumb-interwork
+-# MULTILIB_DIRNAMES   += normal interwork
++MULTILIB_OPTIONS    += mno-thumb-interwork/mthumb-interwork
++MULTILIB_DIRNAMES   += normal interwork
+ # 
+ # MULTILIB_OPTIONS    += fno-leading-underscore/fleading-underscore
+ # MULTILIB_DIRNAMES   += elf under
+diff -Naur gcc-4.9.4/libgcc/config/arm/t-bpabi gcc-4.9.4-fixed/libgcc/config/arm/t-bpabi
+--- gcc-4.9.4/libgcc/config/arm/t-bpabi 2012-08-17 11:06:06.000000000 -0400
++++ gcc-4.9.4-fixed/libgcc/config/arm/t-bpabi   2020-07-01 22:13:39.103762818 -0400
+@@ -17,4 +17,4 @@
+ # On ARM, specifying -fnon-call-exceptions will needlessly pull in
+ # the unwinder in simple programs which use 64-bit division.  Omitting
+ # the option is safe.
+-LIB2_DIVMOD_EXCEPTION_FLAGS := -fexceptions
++LIB2_DIVMOD_EXCEPTION_FLAGS := -fno-exceptions -fno-non-call-exceptions
+diff -Naur gcc-4.9.4/libgcc/Makefile.in gcc-4.9.4-fixed/libgcc/Makefile.in
+--- gcc-4.9.4/libgcc/Makefile.in        2014-01-08 11:37:08.000000000 -0500
++++ gcc-4.9.4-fixed/libgcc/Makefile.in  2020-07-01 22:11:01.199403087 -0400
+@@ -495,7 +495,7 @@
+ ifeq ($(LIB2_DIVMOD_EXCEPTION_FLAGS),)
+ # Provide default flags for compiling divmod functions, if they haven't been
+ # set already by a target-specific Makefile fragment.
+-LIB2_DIVMOD_EXCEPTION_FLAGS := -fexceptions -fnon-call-exceptions
++LIB2_DIVMOD_EXCEPTION_FLAGS := -fno-exceptions -fno-non-call-exceptions
+ endif
+ 
+ # Build LIB2_DIVMOD_FUNCS.
+@@ -816,7 +816,7 @@
+ # libgcc_eh.a, only LIB2ADDEH matters.  If we do, only LIB2ADDEHSTATIC and
+ # LIB2ADDEHSHARED matter.  (Usually all three are identical.)
+ 
+-c_flags := -fexceptions
++c_flags := -fno-exceptions
+ 
+ ifeq ($(enable_shared),yes)
+