riscv64: pass a null argument to ifunc resolvers.
glibc maintainer Florian Weimer pointed out that glibc passes a null first
argument to riscv64 ifunc resolvers. While not super useful right now,
that does make it much easier to switch to providing arguments in future,
such as my favorite idea of passing a default set of hwprobe key/value
pairs, along with a count of how many pairs.
Test: treehugger
Change-Id: Ibe2148dc28aa6ad230e6324b6d725fe472b7ef33
diff --git a/libc/bionic/bionic_call_ifunc_resolver.cpp b/libc/bionic/bionic_call_ifunc_resolver.cpp
index 437de78..410eb78 100644
--- a/libc/bionic/bionic_call_ifunc_resolver.cpp
+++ b/libc/bionic/bionic_call_ifunc_resolver.cpp
@@ -57,6 +57,13 @@
hwcap = getauxval(AT_HWCAP);
}
return reinterpret_cast<ifunc_resolver_t>(resolver_addr)(hwcap);
+#elif defined(__riscv)
+ // This argument and its value is just a placeholder for now,
+ // but it means that if we do pass something in future (such as
+ // getauxval() and/or hwprobe key/value pairs), callees will be able to
+ // recognize what they're being given.
+ typedef ElfW(Addr) (*ifunc_resolver_t)(void*);
+ return reinterpret_cast<ifunc_resolver_t>(resolver_addr)(nullptr);
#else
typedef ElfW(Addr) (*ifunc_resolver_t)(void);
return reinterpret_cast<ifunc_resolver_t>(resolver_addr)();