Code change produced with:

  git ls-files linux-user | \
  xargs sed -i -E 's/(\s+)printf\s*\(("Unhandled.*)\);/\1fprintf(stderr, \2);/g'

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 linux-user/alpha/cpu_loop.c      | 2 +-
 linux-user/cris/cpu_loop.c       | 2 +-
 linux-user/microblaze/cpu_loop.c | 6 +++---
 linux-user/sh4/cpu_loop.c        | 2 +-
 linux-user/sparc/cpu_loop.c      | 2 +-
 5 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/linux-user/alpha/cpu_loop.c b/linux-user/alpha/cpu_loop.c
index b87fcaea87..c1a98c8cbf 100644
--- a/linux-user/alpha/cpu_loop.c
+++ b/linux-user/alpha/cpu_loop.c
@@ -196,7 +196,7 @@ void cpu_loop(CPUAlphaState *env)
             arch_interrupt = false;
             break;
         default:
-            printf ("Unhandled trap: 0x%x\n", trapnr);
+            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
             cpu_dump_state(cs, stderr, fprintf, 0);
             exit(EXIT_FAILURE);
         }
diff --git a/linux-user/cris/cpu_loop.c b/linux-user/cris/cpu_loop.c
index 1c5eca9f83..37bdcfa8cc 100644
--- a/linux-user/cris/cpu_loop.c
+++ b/linux-user/cris/cpu_loop.c
@@ -81,7 +81,7 @@ void cpu_loop(CPUCRISState *env)
             cpu_exec_step_atomic(cs);
             break;
         default:
-            printf ("Unhandled trap: 0x%x\n", trapnr);
+            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
             cpu_dump_state(cs, stderr, fprintf, 0);
             exit(EXIT_FAILURE);
         }
diff --git a/linux-user/microblaze/cpu_loop.c b/linux-user/microblaze/cpu_loop.c
index 5af12d5b21..2af93eb39a 100644
--- a/linux-user/microblaze/cpu_loop.c
+++ b/linux-user/microblaze/cpu_loop.c
@@ -105,8 +105,8 @@ void cpu_loop(CPUMBState *env)
                     queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
                     break;
                 default:
-                    printf("Unhandled hw-exception: 0x%" PRIx64 "\n",
-                           env->sregs[SR_ESR] & ESR_EC_MASK);
+                    fprintf(stderr, "Unhandled hw-exception: 0x%" PRIx64 "\n",
+                            env->sregs[SR_ESR] & ESR_EC_MASK);
                     cpu_dump_state(cs, stderr, fprintf, 0);
                     exit(EXIT_FAILURE);
                     break;
@@ -130,7 +130,7 @@ void cpu_loop(CPUMBState *env)
             cpu_exec_step_atomic(cs);
             break;
         default:
-            printf ("Unhandled trap: 0x%x\n", trapnr);
+            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
             cpu_dump_state(cs, stderr, fprintf, 0);
             exit(EXIT_FAILURE);
         }
diff --git a/linux-user/sh4/cpu_loop.c b/linux-user/sh4/cpu_loop.c
index 418833ea25..fdd348170b 100644
--- a/linux-user/sh4/cpu_loop.c
+++ b/linux-user/sh4/cpu_loop.c
@@ -84,7 +84,7 @@ void cpu_loop(CPUSH4State *env)
             arch_interrupt = false;
             break;
         default:
-            printf ("Unhandled trap: 0x%x\n", trapnr);
+            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
             cpu_dump_state(cs, stderr, fprintf, 0);
             exit(EXIT_FAILURE);
         }
diff --git a/linux-user/sparc/cpu_loop.c b/linux-user/sparc/cpu_loop.c
index 7c4796ca23..91f714afc6 100644
--- a/linux-user/sparc/cpu_loop.c
+++ b/linux-user/sparc/cpu_loop.c
@@ -285,7 +285,7 @@ void cpu_loop (CPUSPARCState *env)
             cpu_exec_step_atomic(cs);
             break;
         default:
-            printf ("Unhandled trap: 0x%x\n", trapnr);
+            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
             cpu_dump_state(cs, stderr, fprintf, 0);
             exit(EXIT_FAILURE);
         }
-- 
2.18.0

On 6 July 2018 at 16:51, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> Code change produced with:
>
>   git ls-files linux-user | \
>   xargs sed -i -E 's/(\s+)printf\s*\(("Unhandled.*)\);/\1fprintf(stderr, \2);/g'
>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  linux-user/alpha/cpu_loop.c      | 2 +-
>  linux-user/cris/cpu_loop.c       | 2 +-
>  linux-user/microblaze/cpu_loop.c | 6 +++---
>  linux-user/sh4/cpu_loop.c        | 2 +-
>  linux-user/sparc/cpu_loop.c      | 2 +-
>  5 files changed, 7 insertions(+), 7 deletions(-)

Makes sense, as we're about to print the cpu_dump_state output to
stderr too.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM