configure | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
The -msoft-float switch is not available in older versions of Clang.
Since we rely on the compiler to not generate floating point instructions
unexpectedly, we block those old compilers now via a test in the configure
script. Note that for some weird reasons, the Clang compiler only complains
about the missing soft-float support if no other flags are passed via
"-Wl,..." to the linker. So we have to use "compile_object" instead of
"compile_prog" for this check.
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
configure | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/configure b/configure
index 676239c697..673419ff31 100755
--- a/configure
+++ b/configure
@@ -5462,7 +5462,7 @@ if test "$cpu" = "s390x" ; then
write_c_skeleton
compile_prog "-march=z900" ""
has_z900=$?
- if [ $has_z900 = 0 ] || compile_prog "-march=z10" ""; then
+ if [ $has_z900 = 0 ] || compile_object "-march=z10 -msoft-float -Werror"; then
if [ $has_z900 != 0 ]; then
echo "WARNING: Your compiler does not support the z900!"
echo " The s390-ccw bios will only work with guest CPUs >= z10."
--
2.27.0
On Tue, 25 May 2021 16:20:32 +0200 Thomas Huth <thuth@redhat.com> wrote: > The -msoft-float switch is not available in older versions of Clang. > Since we rely on the compiler to not generate floating point instructions > unexpectedly, we block those old compilers now via a test in the configure > script. Note that for some weird reasons, the Clang compiler only complains > about the missing soft-float support if no other flags are passed via > "-Wl,..." to the linker. So we have to use "compile_object" instead of > "compile_prog" for this check. Ugh. > > Signed-off-by: Thomas Huth <thuth@redhat.com> > --- > configure | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/configure b/configure > index 676239c697..673419ff31 100755 > --- a/configure > +++ b/configure > @@ -5462,7 +5462,7 @@ if test "$cpu" = "s390x" ; then > write_c_skeleton > compile_prog "-march=z900" "" > has_z900=$? > - if [ $has_z900 = 0 ] || compile_prog "-march=z10" ""; then > + if [ $has_z900 = 0 ] || compile_object "-march=z10 -msoft-float -Werror"; then Do you believe that we should have caught the various clang specialties now? > if [ $has_z900 != 0 ]; then > echo "WARNING: Your compiler does not support the z900!" > echo " The s390-ccw bios will only work with guest CPUs >= z10."
On 25/05/2021 16.31, Cornelia Huck wrote:
> On Tue, 25 May 2021 16:20:32 +0200
> Thomas Huth <thuth@redhat.com> wrote:
>
>> The -msoft-float switch is not available in older versions of Clang.
>> Since we rely on the compiler to not generate floating point instructions
>> unexpectedly, we block those old compilers now via a test in the configure
>> script. Note that for some weird reasons, the Clang compiler only complains
>> about the missing soft-float support if no other flags are passed via
>> "-Wl,..." to the linker. So we have to use "compile_object" instead of
>> "compile_prog" for this check.
>
> Ugh.
It's maybe better to use compile_object for testing -msoft-float anyway
since it could influence the way of linking against libraries (if I get
https://reviews.llvm.org/D72189 right).
>>
>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>> ---
>> configure | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/configure b/configure
>> index 676239c697..673419ff31 100755
>> --- a/configure
>> +++ b/configure
>> @@ -5462,7 +5462,7 @@ if test "$cpu" = "s390x" ; then
>> write_c_skeleton
>> compile_prog "-march=z900" ""
>> has_z900=$?
>> - if [ $has_z900 = 0 ] || compile_prog "-march=z10" ""; then
>> + if [ $has_z900 = 0 ] || compile_object "-march=z10 -msoft-float -Werror"; then
>
> Do you believe that we should have caught the various clang
> specialties now?
Apart from one compiler warning that just popped up today, yes. I'm seeing
this compiler warning with Clang 12.0 now:
roms/SLOF/lib/libnet/ipv6.c:447:18: warning: variable length array folded to
constant array as an extension [-Wgnu-folding-constant]
unsigned short raw[ip6size];
^
... not sure what to do with that one yet.
Thomas
On 5/25/21 4:40 PM, Thomas Huth wrote:
> On 25/05/2021 16.31, Cornelia Huck wrote:
>> On Tue, 25 May 2021 16:20:32 +0200
>> Thomas Huth <thuth@redhat.com> wrote:
>>
>>> The -msoft-float switch is not available in older versions of Clang.
>>> Since we rely on the compiler to not generate floating point
>>> instructions
>>> unexpectedly, we block those old compilers now via a test in the
>>> configure
>>> script. Note that for some weird reasons, the Clang compiler only
>>> complains
>>> about the missing soft-float support if no other flags are passed via
>>> "-Wl,..." to the linker. So we have to use "compile_object" instead of
>>> "compile_prog" for this check.
>>
>> Ugh.
>
> It's maybe better to use compile_object for testing -msoft-float anyway
> since it could influence the way of linking against libraries (if I get
> https://reviews.llvm.org/D72189 right).
>
>>>
>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>> ---
>>> configure | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/configure b/configure
>>> index 676239c697..673419ff31 100755
>>> --- a/configure
>>> +++ b/configure
>>> @@ -5462,7 +5462,7 @@ if test "$cpu" = "s390x" ; then
>>> write_c_skeleton
>>> compile_prog "-march=z900" ""
>>> has_z900=$?
>>> - if [ $has_z900 = 0 ] || compile_prog "-march=z10" ""; then
>>> + if [ $has_z900 = 0 ] || compile_object "-march=z10 -msoft-float
>>> -Werror"; then
>>
>> Do you believe that we should have caught the various clang
>> specialties now?
>
> Apart from one compiler warning that just popped up today, yes. I'm
> seeing this compiler warning with Clang 12.0 now:
>
> roms/SLOF/lib/libnet/ipv6.c:447:18: warning: variable length array
> folded to constant array as an extension [-Wgnu-folding-constant]
> unsigned short raw[ip6size];
> ^
>
> ... not sure what to do with that one yet.
Fix it? =)
Same class as:
https://gitlab.freedesktop.org/slirp/libslirp/-/commit/6690d55626cc
-- >8 --
diff --git a/lib/libnet/ipv6.c b/lib/libnet/ipv6.c
index 6420004..b7daeda 100644
--- a/lib/libnet/ipv6.c
+++ b/lib/libnet/ipv6.c
@@ -441,10 +441,9 @@ static unsigned short ip6_checksum(struct ip6hdr
*ip6h, unsigned char *packet,
{
int i;
unsigned long checksum;
- const int ip6size = sizeof(struct ip6hdr)/sizeof(unsigned short);
union {
struct ip6hdr ip6h;
- unsigned short raw[ip6size];
+ unsigned short raw[sizeof(struct ip6hdr) /
sizeof(unsigned short)];
} pseudo;
memcpy (&pseudo.ip6h, ip6h, sizeof(struct ip6hdr));
@@ -455,7 +454,7 @@ static unsigned short ip6_checksum(struct ip6hdr
*ip6h, unsigned char *packet,
for (checksum = 0, i = 0; i < bytes; i += 2)
checksum += (packet[i] << 8) | packet[i + 1];
- for (i = 0; i < ip6size; i++)
+ for (i = 0; i < sizeof(pseudo.raw); i++)
checksum += pseudo.raw[i];
checksum = (checksum >> 16) + (checksum & 0xffff);
---
Do you want me to send the fix since I have it ready?
On 5/25/21 5:13 PM, Philippe Mathieu-Daudé wrote:
> On 5/25/21 4:40 PM, Thomas Huth wrote:
>> On 25/05/2021 16.31, Cornelia Huck wrote:
>>> On Tue, 25 May 2021 16:20:32 +0200
>>> Thomas Huth <thuth@redhat.com> wrote:
>>>
>>>> The -msoft-float switch is not available in older versions of Clang.
>>>> Since we rely on the compiler to not generate floating point
>>>> instructions
>>>> unexpectedly, we block those old compilers now via a test in the
>>>> configure
>>>> script. Note that for some weird reasons, the Clang compiler only
>>>> complains
>>>> about the missing soft-float support if no other flags are passed via
>>>> "-Wl,..." to the linker. So we have to use "compile_object" instead of
>>>> "compile_prog" for this check.
>>>
>>> Ugh.
>>
>> It's maybe better to use compile_object for testing -msoft-float anyway
>> since it could influence the way of linking against libraries (if I get
>> https://reviews.llvm.org/D72189 right).
>>
>>>>
>>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>>> ---
>>>> configure | 2 +-
>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/configure b/configure
>>>> index 676239c697..673419ff31 100755
>>>> --- a/configure
>>>> +++ b/configure
>>>> @@ -5462,7 +5462,7 @@ if test "$cpu" = "s390x" ; then
>>>> write_c_skeleton
>>>> compile_prog "-march=z900" ""
>>>> has_z900=$?
>>>> - if [ $has_z900 = 0 ] || compile_prog "-march=z10" ""; then
>>>> + if [ $has_z900 = 0 ] || compile_object "-march=z10 -msoft-float
>>>> -Werror"; then
>>>
>>> Do you believe that we should have caught the various clang
>>> specialties now?
>>
>> Apart from one compiler warning that just popped up today, yes. I'm
>> seeing this compiler warning with Clang 12.0 now:
>>
>> roms/SLOF/lib/libnet/ipv6.c:447:18: warning: variable length array
>> folded to constant array as an extension [-Wgnu-folding-constant]
>> unsigned short raw[ip6size];
>> ^
>>
>> ... not sure what to do with that one yet.
See Eric's explanation:
https://www.mail-archive.com/qemu-block@nongnu.org/msg84461.html
>
> Fix it? =)
>
> Same class as:
> https://gitlab.freedesktop.org/slirp/libslirp/-/commit/6690d55626cc
>
> -- >8 --
> diff --git a/lib/libnet/ipv6.c b/lib/libnet/ipv6.c
> index 6420004..b7daeda 100644
> --- a/lib/libnet/ipv6.c
> +++ b/lib/libnet/ipv6.c
> @@ -441,10 +441,9 @@ static unsigned short ip6_checksum(struct ip6hdr
> *ip6h, unsigned char *packet,
> {
> int i;
> unsigned long checksum;
> - const int ip6size = sizeof(struct ip6hdr)/sizeof(unsigned short);
> union {
> struct ip6hdr ip6h;
> - unsigned short raw[ip6size];
> + unsigned short raw[sizeof(struct ip6hdr) /
> sizeof(unsigned short)];
> } pseudo;
>
> memcpy (&pseudo.ip6h, ip6h, sizeof(struct ip6hdr));
> @@ -455,7 +454,7 @@ static unsigned short ip6_checksum(struct ip6hdr
> *ip6h, unsigned char *packet,
> for (checksum = 0, i = 0; i < bytes; i += 2)
> checksum += (packet[i] << 8) | packet[i + 1];
>
> - for (i = 0; i < ip6size; i++)
> + for (i = 0; i < sizeof(pseudo.raw); i++)
> checksum += pseudo.raw[i];
>
> checksum = (checksum >> 16) + (checksum & 0xffff);
> ---
>
> Do you want me to send the fix since I have it ready?
>
On 25/05/2021 17.13, Philippe Mathieu-Daudé wrote:
> On 5/25/21 4:40 PM, Thomas Huth wrote:
>> On 25/05/2021 16.31, Cornelia Huck wrote:
>>> On Tue, 25 May 2021 16:20:32 +0200
>>> Thomas Huth <thuth@redhat.com> wrote:
>>>
>>>> The -msoft-float switch is not available in older versions of Clang.
>>>> Since we rely on the compiler to not generate floating point
>>>> instructions
>>>> unexpectedly, we block those old compilers now via a test in the
>>>> configure
>>>> script. Note that for some weird reasons, the Clang compiler only
>>>> complains
>>>> about the missing soft-float support if no other flags are passed via
>>>> "-Wl,..." to the linker. So we have to use "compile_object" instead of
>>>> "compile_prog" for this check.
>>>
>>> Ugh.
>>
>> It's maybe better to use compile_object for testing -msoft-float anyway
>> since it could influence the way of linking against libraries (if I get
>> https://reviews.llvm.org/D72189 right).
>>
>>>>
>>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>>> ---
>>>> configure | 2 +-
>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/configure b/configure
>>>> index 676239c697..673419ff31 100755
>>>> --- a/configure
>>>> +++ b/configure
>>>> @@ -5462,7 +5462,7 @@ if test "$cpu" = "s390x" ; then
>>>> write_c_skeleton
>>>> compile_prog "-march=z900" ""
>>>> has_z900=$?
>>>> - if [ $has_z900 = 0 ] || compile_prog "-march=z10" ""; then
>>>> + if [ $has_z900 = 0 ] || compile_object "-march=z10 -msoft-float
>>>> -Werror"; then
>>>
>>> Do you believe that we should have caught the various clang
>>> specialties now?
>>
>> Apart from one compiler warning that just popped up today, yes. I'm
>> seeing this compiler warning with Clang 12.0 now:
>>
>> roms/SLOF/lib/libnet/ipv6.c:447:18: warning: variable length array
>> folded to constant array as an extension [-Wgnu-folding-constant]
>> unsigned short raw[ip6size];
>> ^
>>
>> ... not sure what to do with that one yet.
>
> Fix it? =)
>
> Same class as:
> https://gitlab.freedesktop.org/slirp/libslirp/-/commit/6690d55626cc
>
> -- >8 --
> diff --git a/lib/libnet/ipv6.c b/lib/libnet/ipv6.c
> index 6420004..b7daeda 100644
> --- a/lib/libnet/ipv6.c
> +++ b/lib/libnet/ipv6.c
> @@ -441,10 +441,9 @@ static unsigned short ip6_checksum(struct ip6hdr
> *ip6h, unsigned char *packet,
> {
> int i;
> unsigned long checksum;
> - const int ip6size = sizeof(struct ip6hdr)/sizeof(unsigned short);
> union {
> struct ip6hdr ip6h;
> - unsigned short raw[ip6size];
> + unsigned short raw[sizeof(struct ip6hdr) /
> sizeof(unsigned short)];
> } pseudo;
>
> memcpy (&pseudo.ip6h, ip6h, sizeof(struct ip6hdr));
> @@ -455,7 +454,7 @@ static unsigned short ip6_checksum(struct ip6hdr
> *ip6h, unsigned char *packet,
> for (checksum = 0, i = 0; i < bytes; i += 2)
> checksum += (packet[i] << 8) | packet[i + 1];
>
> - for (i = 0; i < ip6size; i++)
> + for (i = 0; i < sizeof(pseudo.raw); i++)
> checksum += pseudo.raw[i];
>
> checksum = (checksum >> 16) + (checksum & 0xffff);
> ---
>
> Do you want me to send the fix since I have it ready?
Yes, please!
Thanks,
Thomas
On Tue, May 25 2021, Thomas Huth <thuth@redhat.com> wrote: > The -msoft-float switch is not available in older versions of Clang. > Since we rely on the compiler to not generate floating point instructions > unexpectedly, we block those old compilers now via a test in the configure > script. Note that for some weird reasons, the Clang compiler only complains > about the missing soft-float support if no other flags are passed via > "-Wl,..." to the linker. So we have to use "compile_object" instead of > "compile_prog" for this check. > > Signed-off-by: Thomas Huth <thuth@redhat.com> > --- > configure | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Thanks, applied.
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