Index: uspace/lib/c/arch/sparc64/Makefile.common
===================================================================
--- uspace/lib/c/arch/sparc64/Makefile.common	(revision 850235d404a93a3e011befe27ef139ef8e288759)
+++ uspace/lib/c/arch/sparc64/Makefile.common	(revision a74d0ad855d5ae331fcd2023dcc2b0281b01e5e9)
@@ -27,5 +27,12 @@
 #
 
-GCC_CFLAGS += -mcpu=ultrasparc -m64 -mcmodel=medlow
+ifeq ($(PROCESSOR),sun4v)
+GCC_CFLAGS += -mcpu=niagara -mno-vis
+else
+GCC_CFLAGS += -mcpu=ultrasparc
+endif
+
+GCC_CFLAGS += -m64 -mcmodel=medlow
+
 LFLAGS = -no-check-sections