Re: [Qemu-devel] [PATCH] tcg: Avoid setting tcg_initialize if !CONFIG_TCG

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

Oops sent a bit too fast.

On 10/26/2017 03:57 PM, Philippe Mathieu-Daudé wrote:
> On 10/26/2017 02:37 PM, Emilio G. Cota wrote:
>> AFAIK the only target that is so far supposed to work with
>> --disable-tcg is i386. The configure script however lets you try to
>> build without TCG if the host has an alternative accelerator (e.g. KVM),
>> but that build is likely to fail. [ just confirmed this with aarch64 ]
> 
> What about s390x?
> 
>   LINK    s390x-softmmu/qemu-system-s390x
> exec.o: In function `tlb_reset_dirty_range_all':
> exec.c:1118: undefined reference to `tlb_reset_dirty'
> exec.o: In function `tcg_commit':
> exec.c:2765: undefined reference to `cpu_reloading_memory_map'
> cpus.o: In function `tcg_cpu_exec':
> cpus.c:1270: undefined reference to `cpu_exec'
> cpus.o: In function `qemu_tcg_rr_cpu_thread_fn':
> cpus.c:1310: undefined reference to `tcg_register_thread'
> cpus.c:1375: undefined reference to `cpu_exec_step_atomic'
> cpus.o: In function `qemu_tcg_cpu_thread_fn':
> cpus.c:1458: undefined reference to `tcg_register_thread'
> cpus.c:1492: undefined reference to `cpu_exec_step_atomic'
> cpus.o: In function `qemu_tcg_init_vcpu':
> cpus.c:1679: undefined reference to `tcg_region_init'
> cpus.c:1689: undefined reference to `parallel_cpus'
> target/s390x/cpu.o: In function `s390_cpu_class_init':
> target/s390x/cpu.c:500: undefined reference to `s390x_translate_init'
> collect2: error: ld returned 1 exit status

bisected to:

b11ec7f2e44b285a3967d629b55d1a6970b06787 is the first bad commit
commit b11ec7f2e44b285a3967d629b55d1a6970b06787
Author: Yang Zhong <yang.zhong@intel.com>
Date:   Mon Jul 3 18:12:21 2017 +0800

    tcg: add CONFIG_TCG guards in headers

    Add CONFIG_TCG around TLB-related functions and structure declarations.
    Some of these functions are defined in ./accel/tcg/cputlb.c, which will
    not be linked in if TCG is disabled, and have no stubs; therefore, their
    callers will also be compiled out for --disable-tcg.

    Signed-off-by: Yang Zhong <yang.zhong@intel.com>
    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>