Avoid gcc warning about casting ptr-to-object to ptr-to-fun

[dougk]

Summary

Use the workaround provided in the dlsym() man page.

[jroelofs]

lib/stats/stats_client.cc

33

IIUC, this should be written as:

void (*LookupSymbolFromMain())(const char *name) {

[dougk]

fix declaration

[zaks.anna]

LGTM

[zaks.anna]

Should I commit or do you have commit access?

[jroelofs]

lib/stats/stats_client.cc

33

erm... never mind. Confusing type is confusing.

A typedef would probably help readability here.

lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc

const char *DemangleSwift(const char *name) {
   // As of now, there are no headers for the Swift runtime. Once they are
   // present, we will weakly link since we do not require Swift runtime to be
   // linked.
   typedef char *(*swift_demangle_ft)(const char *mangledName,
                                      size_t mangledNameLength,
                                      char *outputBuffer,
                                      size_t *outputBufferSize,
                                      uint32_t flags);
-  swift_demangle_ft swift_demangle_f =
-    (swift_demangle_ft) dlsym(RTLD_DEFAULT, "swift_demangle");
+  swift_demangle_ft swift_demangle_f;
+  *(void**)&swift_demangle_f = dlsym(RTLD_DEFAULT, "swift_demangle");
   if (swift_demangle_f)
     return swift_demangle_f(name, internal_strlen(name), 0, 0, 0);
 
   return nullptr;
 }
 
 const char *DemangleSwiftAndCXX(const char *name) {
   CHECK(name);

lib/stats/stats_client.cc

 
 #include "sanitizer_common/sanitizer_internal_defs.h"
 #include "stats/stats.h"
 
 using namespace __sanitizer;
 
 namespace {
 
-void *LookupSymbolFromMain(const char *name) {
+void (*LookupSymbolFromMain(const char *name))() {
 #ifdef _WIN32
-  return reinterpret_cast<void *>(GetProcAddress(GetModuleHandle(0), name));
+  return reinterpret_cast<void (*)()>(GetProcAddress(GetModuleHandle(0), name));
 #else
-  return dlsym(RTLD_DEFAULT, name);
+  void (*f)();
+  *(void**)&f = dlsym(RTLD_DEFAULT, name);
+  return f;
 #endif
 }
 
 StatModule *list;
 
 struct RegisterSanStats {
   unsigned module_id;