Don't call AddDesc() at static init time in LITE_RUNTIME mode.

This patch makes the generation of StaticDescriptorInitializer_$filename$
depend on whether LITE_RUNTIME is enabled. Note that this works only when
extensions are not used.

This lets us significantly decrease the number of static initializers generated
by protoc in LITE_RUNTIME mode (used in Chromium).
In LITE_RUNTIME mode, $adddescriptorsname$() is called the first time that
default_instance() is called (rather than being called during static init).

To benefit from this patch in LITE_RUNTIME mode without extensions, compile
with -DGOOGLE_PROTOBUF_NO_STATIC_INIT.

BUG=351

1 files changed, 22 insertions, 0 deletions

diff --git a/src/google/protobuf/compiler/cpp/cpp_helpers.h b/src/google/protobuf/compiler/cpp/cpp_helpers.h
index b13d53be..662a7c31 100644
--- a/src/google/protobuf/compiler/cpp/cpp_helpers.h
+++ b/src/google/protobuf/compiler/cpp/cpp_helpers.h
@@ -35,12 +35,18 @@
 #ifndef GOOGLE_PROTOBUF_COMPILER_CPP_HELPERS_H__
 #define GOOGLE_PROTOBUF_COMPILER_CPP_HELPERS_H__
 
+#include <map>
 #include <string>
 #include <google/protobuf/descriptor.h>
 #include <google/protobuf/descriptor.pb.h>
 
 namespace google {
 namespace protobuf {
+
+namespace io {
+class Printer;
+}
+
 namespace compiler {
 namespace cpp {
 
@@ -150,6 +156,22 @@ inline bool HasFastArraySerialization(const FileDescriptor* file) {
   return file->options().optimize_for() == FileOptions::SPEED;
 }
 
+// Returns whether we have to generate code with static initializers.
+bool StaticInitializersForced(const FileDescriptor* file);
+
+// Prints 'with_static_init' if static initializers have to be used for the
+// provided file. Otherwise emits both 'with_static_init' and
+// 'without_static_init' using #ifdef.
+void PrintHandlingOptionalStaticInitializers(
+    const FileDescriptor* file, io::Printer* printer,
+    const char* with_static_init, const char* without_static_init,
+    const char* var1 = NULL, const string& val1 = "",
+    const char* var2 = NULL, const string& val2 = "");
+
+void PrintHandlingOptionalStaticInitializers(
+    const map<string, string>& vars, const FileDescriptor* file,
+    io::Printer* printer, const char* with_static_init,
+    const char* without_static_init);
 
 }  // namespace cpp
 }  // namespace compiler