Re: [kvm-unit-tests PATCH] x86: fix build with GCC10

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Wed, 17 Jun 2020 17:21:24 +0200
Vitaly Kuznetsov <vkuznets@redhat.com> wrote:

> kvm-unit-tests fail to build with GCC10:
> 
> /usr/bin/ld: lib/libcflat.a(usermode.o):
>   ./kvm-unit-tests/lib/x86/usermode.c:17:  multiple definition of
> `jmpbuf'; lib/libcflat.a(fault_test.o):
>   ./kvm-unit-tests/lib/x86/fault_test.c:3: first defined here
> 
> It seems that 'jmpbuf' doesn't need to be global in either of these
> files, make it static in both.
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>

I stumbled upon the same issue, and I had independently tested this
exact solution :)

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Tested-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

> ---
>  lib/x86/fault_test.c | 2 +-
>  lib/x86/usermode.c   | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/x86/fault_test.c b/lib/x86/fault_test.c
> index 078dae3da640..e15a21864562 100644
> --- a/lib/x86/fault_test.c
> +++ b/lib/x86/fault_test.c
> @@ -1,6 +1,6 @@
>  #include "fault_test.h"
>  
> -jmp_buf jmpbuf;
> +static jmp_buf jmpbuf;
>  
>  static void restore_exec_to_jmpbuf(void)
>  {
> diff --git a/lib/x86/usermode.c b/lib/x86/usermode.c
> index f01ad9be1799..f0325236dd05 100644
> --- a/lib/x86/usermode.c
> +++ b/lib/x86/usermode.c
> @@ -14,7 +14,7 @@
>  #define USERMODE_STACK_SIZE	0x2000
>  #define RET_TO_KERNEL_IRQ	0x20
>  
> -jmp_buf jmpbuf;
> +static jmp_buf jmpbuf;
>  
>  static void restore_exec_to_jmpbuf(void)
>  {