Forthcoming tcg improvements will diagnose the passed
null pointer with --enable-ubsan:

../src/target/i386/tcg/translate.c:1177:5: runtime error: null pointer passed as argument 3, which is declared to never be null
    #0 ... in gen_setcc ../src/target/i386/tcg/translate.c:1177
    #1 ... in gen_compute_eflags_c ../src/target/i386/tcg/translate.c:1182
    #2 ... in prepare_update_cc_incdec ../src/target/i386/tcg/emit.c.inc:407
    #3 ... in gen_INC ../src/target/i386/tcg/emit.c.inc:2213
    #4 ... in disas_insn ../src/target/i386/tcg/decode-new.c.inc:3151
    #5 ... in i386_tr_translate_insn ../src/target/i386/tcg/translate.c:3514

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/i386/tcg/translate.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index d8de290acb6..192cf43215e 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -891,7 +891,7 @@ static CCPrepare gen_prepare_eflags_c(DisasContext *s, TCGv reg)
 
     case CC_OP_LOGICB ... CC_OP_LOGICQ:
     case CC_OP_POPCNT:
-        return (CCPrepare) { .cond = TCG_COND_NEVER };
+        return (CCPrepare) { .cond = TCG_COND_NEVER, .reg = cpu_cc_dst };
 
     case CC_OP_INCB ... CC_OP_INCQ:
     case CC_OP_DECB ... CC_OP_DECQ:
@@ -965,7 +965,7 @@ static CCPrepare gen_prepare_eflags_s(DisasContext *s, TCGv reg)
         return (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = cpu_cc_src,
                              .imm = CC_S };
     case CC_OP_POPCNT:
-        return (CCPrepare) { .cond = TCG_COND_NEVER };
+        return (CCPrepare) { .cond = TCG_COND_NEVER, .reg = cpu_cc_dst };
     default:
         return gen_prepare_sign_nz(cpu_cc_dst, cc_op_size(s->cc_op));
     }
@@ -982,7 +982,7 @@ static CCPrepare gen_prepare_eflags_o(DisasContext *s, TCGv reg)
     case CC_OP_SBB_SELF:
     case CC_OP_LOGICB ... CC_OP_LOGICQ:
     case CC_OP_POPCNT:
-        return (CCPrepare) { .cond = TCG_COND_NEVER };
+        return (CCPrepare) { .cond = TCG_COND_NEVER, .reg = cpu_cc_dst };
     case CC_OP_MULB ... CC_OP_MULQ:
         return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src };
     default:
-- 
2.53.0

On 15/9/26 00:00, Richard Henderson wrote:
> Forthcoming tcg improvements will diagnose the passed
> null pointer with --enable-ubsan:
> 
> ../src/target/i386/tcg/translate.c:1177:5: runtime error: null pointer passed as argument 3, which is declared to never be null
>      #0 ... in gen_setcc ../src/target/i386/tcg/translate.c:1177
>      #1 ... in gen_compute_eflags_c ../src/target/i386/tcg/translate.c:1182
>      #2 ... in prepare_update_cc_incdec ../src/target/i386/tcg/emit.c.inc:407
>      #3 ... in gen_INC ../src/target/i386/tcg/emit.c.inc:2213
>      #4 ... in disas_insn ../src/target/i386/tcg/decode-new.c.inc:3151
>      #5 ... in i386_tr_translate_insn ../src/target/i386/tcg/translate.c:3514
> 
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>   target/i386/tcg/translate.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com>