skip recording policy name in computeStats when RTTI is disabled

Summary:
If RTTI is disabled for the compilation unit, simply skip recording the type of
F14Policy in computeStats.

This diff also contains a few fixes for when folly is built without RTTI.

Reviewed By: nbronson

Differential Revision: D8523618

fbshipit-source-id: dfbfa93ec462c0ff72c06b9f65d61b081e361f41

folly/ExceptionString.h

@@ -62,7 +62,8 @@ auto exceptionStr(const E& e) -> typename std::
 #ifdef FOLLY_HAS_RTTI
   return demangle(typeid(e));
 #else
-  return "Exception (no RTTI available)";
+  (void)e;
+  return "Exception (no RTTI available) ";
 #endif
 }
 

folly/container/detail/F14Table.h

@@ -2157,7 +2157,9 @@ class F14Table : public Policy {
     FOLLY_SAFE_DCHECK(n1 == size(), "");
     FOLLY_SAFE_DCHECK(n2 == size(), "");
 
+#if FOLLY_HAS_RTTI
     stats.policy = typeid(Policy).name();
+#endif
     stats.size = size();
     stats.valueSize = sizeof(value_type);
     stats.bucketCount = bucket_count();

folly/container/test/F14TestUtil.h

@@ -432,7 +432,13 @@ std::ostream& operator<<(std::ostream& xo, F14TableStats const& stats) {
   using f14::Histo;
 
   xo << "{ " << std::endl;
-  xo << "  policy: " << folly::demangle(stats.policy) << std::endl;
+  xo << "  policy: "
+#if FOLLY_HAS_RTTI
+     << folly::demangle(stats.policy)
+#else
+     << "unknown (RTTI not availabe)"
+#endif
+     << std::endl;
   xo << "  size: " << stats.size << std::endl;
   xo << "  valueSize: " << stats.valueSize << std::endl;
   xo << "  bucketCount: " << stats.bucketCount << std::endl;

folly/experimental/symbolizer/Symbolizer.cpp

@@ -320,7 +320,7 @@ void SymbolizePrinter::println(
 namespace {
 
 int getFD(const std::ios& stream) {
-#ifdef __GNUC__
+#if defined(__GNUC__) && FOLLY_HAS_RTTI
   std::streambuf* buf = stream.rdbuf();
   using namespace __gnu_cxx;
 
@@ -336,6 +336,8 @@ int getFD(const std::ios& stream) {
       return sbuf->fd();
     }
   }
+#else
+  (void)stream;
 #endif // __GNUC__
   return -1;
 }