When -march=native is passed to host_detect_local_cpu to the backend,
it overrides all command lines after it. That means
$ gcc -march=native -march=armv8-a
is treated as
$ gcc -march=armv8-a -march=native
Prune joined switches with Negative and RejectNegative to allow
-march=armv8-a to override previous -march=native on command-line.
This is the same fix as was applied for i386 in SVN revision 269164 but for
aarch64 and arm.
gcc/
PR driver/69471
* config/aarch64/aarch64.opt (march=): Add Negative(march=).
(mtune=): Add Negative(mtune=).
* config/arm/arm.opt: Likewise.
---
gcc/config/aarch64/aarch64.opt | 5 +++--
gcc/config/arm/arm.opt | 4 ++--
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/gcc/config/aarch64/aarch64.opt b/gcc/config/aarch64/aarch64.opt
index 865b6a6d8ca..908dca23b3c 100644
--- a/gcc/config/aarch64/aarch64.opt
+++ b/gcc/config/aarch64/aarch64.opt
@@ -119,7 +119,8 @@ EnumValue
Enum(aarch64_tls_size) String(48) Value(48)
march=
-Target RejectNegative ToLower Joined Var(aarch64_arch_string)
+Target RejectNegative Negative(march=) ToLower Joined Var(aarch64_arch_string)
+
Use features of architecture ARCH.
mcpu=
@@ -127,7 +128,7 @@ Target RejectNegative ToLower Joined Var(aarch64_cpu_string)
Use features of and optimize for CPU.
mtune=
-Target RejectNegative ToLower Joined Var(aarch64_tune_string)
+Target RejectNegative Negative(mtune=) ToLower Joined Var(aarch64_tune_string)
Optimize for CPU.
mabi=
diff --git a/gcc/config/arm/arm.opt b/gcc/config/arm/arm.opt
index 452f0cf6d67..e3ead5c95d1 100644
--- a/gcc/config/arm/arm.opt
+++ b/gcc/config/arm/arm.opt
@@ -82,7 +82,7 @@ mapcs-stack-check
Target Report Mask(APCS_STACK) Undocumented
march=
-Target RejectNegative ToLower Joined Var(arm_arch_string)
+Target RejectNegative Negative(march=) ToLower Joined Var(arm_arch_string)
Specify the name of the target architecture.
; Other arm_arch values are loaded from arm-tables.opt
@@ -232,7 +232,7 @@ Target Report Mask(TPCS_LEAF_FRAME)
Thumb: Generate (leaf) stack frames even if not needed.
mtune=
-Target RejectNegative ToLower Joined Var(arm_tune_string)
+Target RejectNegative Negative(mtune=) ToLower Joined Var(arm_tune_string)
Tune code for the given processor.
mprint-tune-info
--
2.21.0
