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 <th...@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 <th...@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
