[PATCH 3/3] dma/idxd: fix non-AVX builds with older compilers

[Bruce Richardson]

When building without AVX2 support using an older compiler e.g. gcc 4.8
on Centos/RHEL 7, we get build errors due to the use of AVX2 intrinsics.
This is because the compiler does not support
"__attribute__((target(AVX2)))" function attribute. Disable build of
this driver such edge cases.

Generic builds using recent compilers, and all builds with a minimum
baseline of AVX2 are unaffected by this change.

Fixes: aa802b10237c ("dma/idxd: fix AVX2 in non-datapath functions")

Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
---
 drivers/dma/idxd/meson.build | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/dma/idxd/meson.build b/drivers/dma/idxd/meson.build
index dcc0a297d7..c5403b431c 100644
--- a/drivers/dma/idxd/meson.build
+++ b/drivers/dma/idxd/meson.build
@@ -4,6 +4,17 @@
 build = dpdk_conf.has('RTE_ARCH_X86')
 reason = 'only supported on x86'

+test_avx2_code = '''
+#include <x86intrin.h>
+__attribute__((target("avx2")))
+__m256i fn(void *x) { return _mm256_loadu_si256(x); }
+'''
+if build and not cc.compiles(test_avx2_code, args:machine_args)
+    build = false
+    reason = 'missing support for AVX2 function attribute'
+    subdir_done()
+endif
+
 deps += ['bus_pci']
 sources = files(
         'idxd_common.c',
--
2.34.1