Improved check for trivial templates.

tools/clang/plugins/FindBadConstructsConsumer.cpp

Index: tools/clang/plugins/FindBadConstructsConsumer.cpp
diff --git a/tools/clang/plugins/FindBadConstructsConsumer.cpp b/tools/clang/plugins/FindBadConstructsConsumer.cpp
index 3c12e9f50c77668ee862b6d27e778064c39eab45..c19b66b614a2f2829d5139513bb783c212b40399 100644
--- a/tools/clang/plugins/FindBadConstructsConsumer.cpp
+++ b/tools/clang/plugins/FindBadConstructsConsumer.cpp
@@ -650,6 +650,7 @@ void FindBadConstructsConsumer::CountType(const Type* type,
       TemplateName name =
           dyn_cast<TemplateSpecializationType>(type)->getTemplateName();
       bool whitelisted_template = false;
+      bool trivial_template = false;
 
       // HACK: I'm at a loss about how to get the syntax checker to get
       // whether a template is externed or not. For the first pass here,
@@ -660,11 +661,17 @@ void FindBadConstructsConsumer::CountType(const Type* type,
       // fix. https://bugs.chromium.org/p/chromium/issues/detail?id=663463
       if (TemplateDecl* decl = name.getAsTemplateDecl()) {
         std::string base_name = decl->getNameAsString();
-        if (base_name == "basic_string" || base_name == "atomic_int")
+        if (base_name == "basic_string")
           whitelisted_template = true;
+        else if (base_name == "__atomic_int" || base_name == "atomic_int" ||
+                 base_name == "__atomic_base") {

[dcheng, 2016/11/09 06:33:45]

I'm wondering if we should just intercept this in Type::Typedef: the standard
defines atomic_int to be a typedef for atomic<int>, so it might be more robust
than trying to match against implementation-specified names?

[hans, 2016/11/09 16:48:00]

(Actually, the standard says atomic_int is either a typedef to the
specialization or to a base class of it.)

But yeah, if we could check the name of the typedef that might be better.

[palmer, 2016/11/10 00:25:22]

Done (and that resulted in a smaller diff, which is always nice).

+          trivial_template = true;
+        }
       }
 
-      if (whitelisted_template)
+      if (trivial_template)
+        (*trivial_member)++;
+      else if (whitelisted_template)
         (*non_trivial_member)++;
       else
         (*templated_non_trivial_member)++;