diff --git a/repos/os/src/drivers/ahci/ata_protocol.h b/repos/os/src/drivers/ahci/ata_protocol.h
index b8abccb9d2..c99e5f3197 100644
--- a/repos/os/src/drivers/ahci/ata_protocol.h
+++ b/repos/os/src/drivers/ahci/ata_protocol.h
@@ -312,8 +312,8 @@ class Ata::Protocol : public Ahci::Protocol, Noncopyable
 
 			*r = request;
 
-			size_t slot         = _slots.index(*r);
-			_slot_states       |= 1u << slot;
+			auto const slot  = unsigned(_slots.index(*r));
+			_slot_states    |= 1u << slot;
 
 			/* setup fis */
 			Command_table table(port.command_table_range(slot),
diff --git a/repos/os/src/drivers/ahci/target.mk b/repos/os/src/drivers/ahci/target.mk
index 7d22e9a0dd..6b73696a0b 100644
--- a/repos/os/src/drivers/ahci/target.mk
+++ b/repos/os/src/drivers/ahci/target.mk
@@ -3,6 +3,4 @@ SRC_CC  += main.cc
 INC_DIR += $(PRG_DIR)
 LIBS    += base
 
-CC_CXX_WARN_STRICT_CONVERSION =
-
 vpath %.cc $(PRG_DIR)