powerpc/xmon: Fix opcode being uninitialized in print_insn_powerpc

When building with -Wsometimes-uninitialized, Clang warns:

  arch/powerpc/xmon/ppc-dis.c:157:7: warning: variable 'opcode' is used
  uninitialized whenever 'if' condition is false
  [-Wsometimes-uninitialized]
    if (cpu_has_feature(CPU_FTRS_POWER9))
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  arch/powerpc/xmon/ppc-dis.c:167:7: note: uninitialized use occurs here
    if (opcode == NULL)
        ^~~~~~
  arch/powerpc/xmon/ppc-dis.c:157:3: note: remove the 'if' if its
  condition is always true
    if (cpu_has_feature(CPU_FTRS_POWER9))
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  arch/powerpc/xmon/ppc-dis.c:132:38: note: initialize the variable
  'opcode' to silence this warning
    const struct powerpc_opcode *opcode;
                                       ^
                                        = NULL
  1 warning generated.

This warning seems to make no sense on the surface because opcode is set
to NULL right below this statement. However, there is a comma instead of
semicolon to end the dialect assignment, meaning that the opcode
assignment only happens in the if statement. Properly terminate that
line so that Clang no longer warns.

Fixes: 5b102782c7 ("powerpc/xmon: Enable disassembly files (compilation changes)")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Nathan Chancellor 2019-02-25 22:38:55 -07:00 committed by Michael Ellerman
parent 75d9fc7fd9
commit e7140639b1

View File

@ -158,7 +158,7 @@ int print_insn_powerpc (unsigned long insn, unsigned long memaddr)
dialect |= (PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6 | PPC_OPCODE_POWER7
| PPC_OPCODE_POWER8 | PPC_OPCODE_POWER9 | PPC_OPCODE_HTM
| PPC_OPCODE_ALTIVEC | PPC_OPCODE_ALTIVEC2
| PPC_OPCODE_VSX | PPC_OPCODE_VSX3),
| PPC_OPCODE_VSX | PPC_OPCODE_VSX3);
/* Get the major opcode of the insn. */
opcode = NULL;