queue-4.19/powerpc-xmon-fix-opcode-being-uninitialized-in-print.patch

   1 From 3405de2d79b9c33ae5b60280b906a50c48b6199f Mon Sep 17 00:00:00 2001
   2 From: Nathan Chancellor <natechancellor@gmail.com>
   3 Date: Mon, 25 Feb 2019 22:38:55 -0700
   4 Subject: powerpc/xmon: Fix opcode being uninitialized in print_insn_powerpc
   5
   6 [ Upstream commit e7140639b1de65bba435a6bd772d134901141f86 ]
   7
   8 When building with -Wsometimes-uninitialized, Clang warns:
   9
  10   arch/powerpc/xmon/ppc-dis.c:157:7: warning: variable 'opcode' is used
  11   uninitialized whenever 'if' condition is false
  12   [-Wsometimes-uninitialized]
  13     if (cpu_has_feature(CPU_FTRS_POWER9))
  14         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  15   arch/powerpc/xmon/ppc-dis.c:167:7: note: uninitialized use occurs here
  16     if (opcode == NULL)
  17         ^~~~~~
  18   arch/powerpc/xmon/ppc-dis.c:157:3: note: remove the 'if' if its
  19   condition is always true
  20     if (cpu_has_feature(CPU_FTRS_POWER9))
  21     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  22   arch/powerpc/xmon/ppc-dis.c:132:38: note: initialize the variable
  23   'opcode' to silence this warning
  24     const struct powerpc_opcode *opcode;
  25                                        ^
  26                                         = NULL
  27   1 warning generated.
  28
  29 This warning seems to make no sense on the surface because opcode is set
  30 to NULL right below this statement. However, there is a comma instead of
  31 semicolon to end the dialect assignment, meaning that the opcode
  32 assignment only happens in the if statement. Properly terminate that
  33 line so that Clang no longer warns.
  34
  35 Fixes: 5b102782c7f4 ("powerpc/xmon: Enable disassembly files (compilation changes)")
  36 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
  37 Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
  38 Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
  39 Signed-off-by: Sasha Levin <sashal@kernel.org>
  40 ---
  41  arch/powerpc/xmon/ppc-dis.c | 2 +-
  42  1 file changed, 1 insertion(+), 1 deletion(-)
  43
  44 diff --git a/arch/powerpc/xmon/ppc-dis.c b/arch/powerpc/xmon/ppc-dis.c
  45 index 9deea5ee13f6..27f1e6415036 100644
  46 --- a/arch/powerpc/xmon/ppc-dis.c
  47 +++ b/arch/powerpc/xmon/ppc-dis.c
  48 @@ -158,7 +158,7 @@ int print_insn_powerpc (unsigned long insn, unsigned long memaddr)
  49      dialect |= (PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6 | PPC_OPCODE_POWER7
  50                 | PPC_OPCODE_POWER8 | PPC_OPCODE_POWER9 | PPC_OPCODE_HTM
  51                 | PPC_OPCODE_ALTIVEC | PPC_OPCODE_ALTIVEC2
  52 -               | PPC_OPCODE_VSX | PPC_OPCODE_VSX3),
  53 +               | PPC_OPCODE_VSX | PPC_OPCODE_VSX3);
  54
  55    /* Get the major opcode of the insn.  */
  56    opcode = NULL;
  57 --
  58 2.19.1
  59