releases/4.9.135/arc-build-get-rid-of-toolchain-check.patch

   1 From 615f64458ad890ef94abc879a66d8b27236e733a Mon Sep 17 00:00:00 2001
   2 From: Alexey Brodkin <abrodkin@synopsys.com>
   3 Date: Thu, 13 Sep 2018 23:24:28 +0300
   4 Subject: ARC: build: Get rid of toolchain check
   5
   6 From: Alexey Brodkin <abrodkin@synopsys.com>
   7
   8 commit 615f64458ad890ef94abc879a66d8b27236e733a upstream.
   9
  10 This check is very naive: we simply test if GCC invoked without
  11 "-mcpu=XXX" has ARC700 define set. In that case we think that GCC
  12 was built with "--with-cpu=arc700" and has libgcc built for ARC700.
  13
  14 Otherwise if ARC700 is not defined we think that everythng was built
  15 for ARCv2.
  16
  17 But in reality our life is much more interesting.
  18
  19 1. Regardless of GCC configuration (i.e. what we pass in "--with-cpu"
  20    it may generate code for any ARC core).
  21
  22 2. libgcc might be built with explicitly specified "--mcpu=YYY"
  23
  24 That's exactly what happens in case of multilibbed toolchains:
  25  - GCC is configured with default settings
  26  - All the libs built for many different CPU flavors
  27
  28 I.e. that check gets in the way of usage of multilibbed
  29 toolchains. And even non-multilibbed toolchains are affected.
  30 OpenEmbedded also builds GCC without "--with-cpu" because
  31 each and every target component later is compiled with explicitly
  32 set "-mcpu=ZZZ".
  33
  34 Acked-by: Rob Herring <robh@kernel.org>
  35 Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
  36 Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
  37 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  38
  39 ---
  40  arch/arc/Makefile |   14 --------------
  41  1 file changed, 14 deletions(-)
  42
  43 --- a/arch/arc/Makefile
  44 +++ b/arch/arc/Makefile
  45 @@ -22,20 +22,6 @@ cflags-y     += -fno-common -pipe -fno-built
  46  cflags-$(CONFIG_ISA_ARCOMPACT) += -mA7
  47  cflags-$(CONFIG_ISA_ARCV2)     += -mcpu=archs
  48
  49 -is_700 = $(shell $(CC) -dM -E - < /dev/null | grep -q "ARC700" && echo 1 || echo 0)
  50 -
  51 -ifdef CONFIG_ISA_ARCOMPACT
  52 -ifeq ($(is_700), 0)
  53 -    $(error Toolchain not configured for ARCompact builds)
  54 -endif
  55 -endif
  56 -
  57 -ifdef CONFIG_ISA_ARCV2
  58 -ifeq ($(is_700), 1)
  59 -    $(error Toolchain not configured for ARCv2 builds)
  60 -endif
  61 -endif
  62 -
  63  ifdef CONFIG_ARC_CURR_IN_REG
  64  # For a global register defintion, make sure it gets passed to every file
  65  # We had a customer reported bug where some code built in kernel was NOT using