Thread (12 messages) 12 messages, 4 authors, 2021-06-23

Re: [dpdk-dev] [PATCH v2] build: fix SVE compile error with gcc8.3

From: Bruce Richardson <hidden>
Date: 2021-05-20 13:09:14

On Thu, May 20, 2021 at 07:40:12PM +0800, Chengwen Feng wrote:
If the target machine has SVE feature (e.g. "-march=armv8.2-a+sve'),
and the compiler is gcc8.3, it will compile error:
	In file included from ../dpdk-next-net/lib/eal/common/
	eal_common_options.c:38:
	../dpdk-next-net/lib/eal/arm/include/rte_vect.h:13:10: fatal
	error: arm_sve.h: No such file or directory
	#include <arm_sve.h>
	       ^~~~~~~~~~~
	compilation terminated.

The root cause is that gcc8.3 support SVE (the macro __ARM_FEATURE_SVE
was 1), but it doesn't support SVE ACLE [1].

The solution:
a) Detect compiler whether support SVE ACLE, if support then define
CC_SVE_ACLE_SUPPORT macro.
b) Use the CC_SVE_ACLE_SUPPORT macro to include SVE header file.

[1] ACLE:  Arm C Language Extensions, the SVE ACLE header file is
<arm_sve.h>, user should include it when writing ACLE SVE code.

Fixes: 67b68824a82d ("lpm/arm: support SVE")

Signed-off-by: Chengwen Feng <redacted>
---
v2: 
* modify title start with 'build'
One minor comment inline below.
/Bruce
quoted hunk ↗ jump to hunk
---
 config/arm/meson.build         | 5 +++++
 lib/eal/arm/include/rte_vect.h | 2 +-
 lib/lpm/rte_lpm.h              | 2 +-
 3 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/config/arm/meson.build b/config/arm/meson.build
index e83a56e..bff70e4 100644
--- a/config/arm/meson.build
+++ b/config/arm/meson.build
@@ -480,6 +480,11 @@ if (cc.get_define('__ARM_NEON', args: machine_args) != '' or
     compile_time_cpuflags += ['RTE_CPUFLAG_NEON']
 endif
 
+if (cc.get_define('__ARM_FEATURE_SVE', args: machine_args) != '' and
+    cc.check_header('arm_sve.h'))
Please double-indent this line. It looks like part of the condition body
as-is.
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help