diff --git a/include/arch/aarch64/arch.h b/include/arch/aarch64/arch.h
index 85546ec..58abd44 100644
--- a/include/arch/aarch64/arch.h
+++ b/include/arch/aarch64/arch.h
@@ -1335,4 +1335,7 @@
 #define CPUMPMMCR_EL3_MPMM_EN_SHIFT	UINT64_C(0)
 #define CPUMPMMCR_EL3_MPMM_EN_MASK	UINT64_C(0x1)
 
+/* alternative system register encoding for the "sb" speculation barrier */
+#define SYSREG_SB			S0_3_C3_C0_7
+
 #endif /* ARCH_H */
diff --git a/include/arch/aarch64/asm_macros.S b/include/arch/aarch64/asm_macros.S
index 66c39e5..b4dab08 100644
--- a/include/arch/aarch64/asm_macros.S
+++ b/include/arch/aarch64/asm_macros.S
@@ -215,12 +215,24 @@
 	.endm
 
 	/*
+	 * The "sb" instruction was introduced later into the architecture,
+	 * so not all toolchains understand it. Some deny its usage unless
+	 * a supported processor is specified on the build command line.
+	 * Use sb's system register encoding to work around this, we already
+	 * guard the sb execution with a feature flag.
+	 */
+
+	.macro sb_barrier_insn
+	msr	SYSREG_SB, xzr
+	.endm
+
+	/*
 	 * Macro for using speculation barrier instruction introduced by
 	 * FEAT_SB, if it's enabled.
 	 */
 	.macro speculation_barrier
 #if ENABLE_FEAT_SB
-	sb
+	sb_barrier_insn
 #else
 	dsb	sy
 	isb
@@ -234,7 +246,7 @@
 	.macro exception_return
 	eret
 #if ENABLE_FEAT_SB
-	sb
+	sb_barrier_insn
 #else
 	dsb	nsh
 	isb