Re: [Qemu-devel] [PATCH] configure: Automatically fall back to TCI on non-release architectures

[Helge Deller]

Hi Philippe,

On 04.04.19 21:24, Philippe Mathieu-Daudé wrote:
> Hi Helge,
>
> On 4/4/19 8:57 PM, Helge Deller wrote:
>> If a non-release architecture is found, and it's known that there is no
>> native TCG support for that CPU, automatically fall back to the TCI
>> implementation instead of requesting the user to run configure again
>> with the --enable-tcg-interpreter option.
>>
>> This change simplifies building qemu in automatic build environments
>> (like in my case the debian buildds) because one does not need to
>> special case on the architectures.
>>
>> Signed-off-by: Helge Deller <address@hidden>
>>
>> diff --git a/configure b/configure
>> index 1c563a7027..8fe4fc84d8 100755
>> --- a/configure
>> +++ b/configure
>> @@ -769,8 +769,10 @@ case "$cpu" in
>>      cross_cc_sparc=$host_cc
>>    ;;
>>    *)
>> -    # This will result in either an error or falling back to TCI later
>> +    # Fall back to TCI on unsupported CPUs
>>      ARCH=unknown
>> +    echo "Unsupported '$cpu' CPU found. Will use TCG with TCI 
>> (experimental)."
>> +    tcg_interpreter="yes"
>
> I'm not comfortable with this change... I'd prefer to keep the explicit
> flag. Is your debian buildd targetting mainstream QEMU or the Debian
> package? Can't you manage this as a Debian specific patch?

I tried to get it added as debian specific patch a few times.

> Else, why not add a "hppa" case selecting TCI in the switch? This would
> be less invasive.

If that would be acceptable, I'm happy to send a new patch.

Helge

>>    ;;
>>  esac
>>  if test -z "$ARCH"; then
>> @@ -1855,16 +1857,6 @@ if ! compile_prog ; then
>>      error_exit "\"$cc\" cannot build an executable (is your linker broken?)"
>>  fi
>>
>> -# Now we have handled --enable-tcg-interpreter and know we're not just
>> -# printing the help message, bail out if the host CPU isn't supported.
>> -if test "$ARCH" = "unknown"; then
>> -    if test "$tcg_interpreter" = "yes" ; then
>> -        echo "Unsupported CPU = $cpu, will use TCG with TCI (experimental)"
>> -    else
>> -        error_exit "Unsupported CPU = $cpu, try --enable-tcg-interpreter"
>> -    fi
>> -fi
>> -
>>  # Consult white-list to determine whether to enable werror
>>  # by default.  Only enable by default for git builds
>>  if test -z "$werror" ; then
>>