Make sure we always add signature to `fp$` functions (#1994)

Previously we were searching for the function by name but this
doesn't work when the internal name for the function is different.

In order to repro such a case the shared.c test was converted to C++
since then binaryen's internal name is different since it comes from
the de-mangled name section.

1 files changed, 10 insertions, 0 deletions

diff --git a/test/lld/shared.cpp b/test/lld/shared.cpp
new file mode 100644
index 000000000..51bdee833
--- /dev/null
+++ b/test/lld/shared.cpp
@@ -0,0 +1,10 @@
+extern "C" int puts(const char* str);
+extern "C" int external_var;
+
+int print_message() {
+  puts("Hello, world");
+  return external_var;
+}
+
+void* ptr_puts = (void*)&puts;
+void* ptr_local_func = (void*)&print_message;