diff --git a/makefiles/toolchain/llvm.inc.mk b/makefiles/toolchain/llvm.inc.mk
index 4cf21d361b..496c3c0d39 100644
--- a/makefiles/toolchain/llvm.inc.mk
+++ b/makefiles/toolchain/llvm.inc.mk
@@ -72,6 +72,18 @@ ifneq (,$(TARGET_ARCH))
   CXXINCLUDES += $(GCC_CXX_INCLUDES)
 endif
 
+# For bare metal targets the performance penalty of atomic operations being
+# implemented with library calls is totally insignificant. In case LTO is
+# is enabled, the overhead compared to manually disabling interrupts is fully
+# optimized out (unless atomic operations could be grouped together to a single
+# critical section). So there is - in our use case - no value in having the
+# warning
+CFLAGS += -Wno-atomic-alignment
+
+# For compatibility with older clang versions we also disable warnings on
+# unsupported warning flags:
+CFLAGS += -Wno-unknown-warning-option
+
 OPTIONAL_CFLAGS_BLACKLIST += -fno-delete-null-pointer-checks
 OPTIONAL_CFLAGS_BLACKLIST += -Wformat-overflow
 OPTIONAL_CFLAGS_BLACKLIST += -Wformat-truncation