I recently noticed that the GCC 'resolver' attribute used for ifunc's is not
on by default for aarch64 even though all the infrastructure to support it is
in place. I made memcpy an ifunc on aarch64 in glibc and am looking at
possibly using it for libatomic too. For this reason I would like to enable
it by default. Note that the memcpy ifunc works even when this is not enabled
because glibc enables ifuncs by using the assembly language .type psuedo-op to
set the resolver attribute when GCC cannot do it with an attribute. Using
an ifunc in libatomic does require this to be enabled and I do not see any
reason not to have it enabled by default.
Tested with no regressions, OK to check in?
Steve Ellcey
sell...@cavium.com
2017-06-12 Steve Ellcey <sell...@cavium.com>
* config.gcc (aarch64*-*-linux*): Enable IFUNC by default.
diff --git a/gcc/config.gcc b/gcc/config.gcc
index a311cd95..e4caca4 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -974,6 +974,7 @@ aarch64*-*-freebsd*)
tmake_file="${tmake_file} aarch64/t-aarch64 aarch64/t-aarch64-freebsd"
;;
aarch64*-*-linux*)
+ default_gnu_indirect_function=yes
tm_file="${tm_file} dbxelf.h elfos.h gnu-user.h linux.h glibc-stdint.h"
tm_file="${tm_file} aarch64/aarch64-elf.h aarch64/aarch64-linux.h"
tmake_file="${tmake_file} aarch64/t-aarch64 aarch64/t-aarch64-linux"
