510491 - Adding 'instantiated from' support in dehydra?

Status: RESOLVED WONTFIX

(Developer Infrastructure :: Source Code Analysis, defect)

Description

[Diego Novillo]

When our analysis discovers an error with template instantiation.  When we see a "bad" instantiation:

foo.h:
enum MyEnum { EnumVal21, EnumVal22 };

template<typename FOO>
class MyTemplateClass {
 public:
  MyTemplateClass(FOO a) { a_ = a; }
  FOO a() { return a_; }
 private:
  FOO a_;
};


foo.cc:
MyTemplateClass<MyEnum> templateclass2(EnumVal21);

where MyEnum is an analysis violation, the error is flagged in
foo.h instead of foo.cc.  We would like to be able to flag it at
foo.cc.  Probably following GCC's "instantiated from here"
messages:

foo.h:3: error: Type MyEnum is wonky.
foo.cc:1: instantiated from here.

However, it does not seem that dehydra collects enough locus
information to provide that.

Would this be hard to add?  Where should I start looking?

Comment 1

[(dormant account)]

I think you are talking about taking .loc information pulled from ASTs and you'd like to be able to be get more info on it. This should be easy as dehydra has a special location type that keeps gcc's underlying location id.

loc.name and .line/col are lazily computed. So you'd add another property for locus stuff.

http://hg.mozilla.org/rewriting-and-analysis/dehydra/file/ab8be6feaf50/dehydra.c#l327

This would be a very useful feature to have, I've been wanting to expose that for a while, but never got around to it.

Comment 2

[Joshua Cranmer [:jcranmer]]

Dehydra and treehydra are no longer maintained by Mozilla.