Apple Clang requires +sme in the arch string for M4

Author: martin-frbg

kernel/Makefile

@@ -36,14 +36,18 @@ ifeq ($(TARGET_CORE), ARMV9SME)
 endif
 ifeq ($(TARGET_CORE), VORTEXM4)
   ifeq ($(C_COMPILER), GCC)
- override CFLAGS += -DBUILD_KERNEL -DTABLE_NAME=gotoblas_$(TARGET_CORE) -UHAVE_SME -march=armv8.4-a
+    override CFLAGS += -DBUILD_KERNEL -DTABLE_NAME=gotoblas_$(TARGET_CORE) -UHAVE_SME -march=armv8.4-a
   else
- override CFLAGS += -DBUILD_KERNEL -DTABLE_NAME=gotoblas_$(TARGET_CORE) -march=armv8.4-a -mcpu=apple-m4
-   ifdef OS_WINDOWS
-   ifeq ($(C_COMPILER), CLANG)
-   override CFLAGS += --aarch64-stack-hazard-size=0
-   endif
-   endif
+    ifeq ($(APPLECLANG),1)
+      override CFLAGS += -DBUILD_KERNEL -DTABLE_NAME=gotoblas_$(TARGET_CORE) -march=armv8.4-a+sme -mcpu=apple-m4
+    else
+      override CFLAGS += -DBUILD_KERNEL -DTABLE_NAME=gotoblas_$(TARGET_CORE) -march=armv8.4-a -mcpu=apple-m4
+    endif
+    ifdef OS_WINDOWS
+      ifeq ($(C_COMPILER), CLANG)
+        override CFLAGS += --aarch64-stack-hazard-size=0
+      endif
+    endif
   endif
 endif
 ifeq ($(TARGET_CORE), SAPPHIRERAPIDS)