Problems with type qualifiers around typedefs

[john-h-kastner]

In some cases type qualifiers are dropped:

typedef int foo;
const foo *a;

converts to

typedef int foo;
_Ptr<foo> a = ((void *)0);

Other times the type qualifier can be moved inside the typdef:

typedef int *bar;
const bar b;

converts to

typedef const _Ptr<int> bar;
bar b = ((void *)0);

[john-h-kastner]

After looking at this briefly, the first problem should be fixable by adding the type qualifier to the string constructed by mkString for the base type in the typedef case.

checkedc-clang/clang/lib/3C/ConstraintVariables.cpp

Lines 788 to 790 in 960bf35

	} else if (typedeflevelinfo.hasTypedef) {
	auto name = typedeflevelinfo.typedefName;
	Ss << name;

The second problem is more difficult. I think that typedefs don't get their own constraint variable right now, so a typdef declaration is rewritten based on one of the variable declaration that uses it. This is fine for the purpose of checked/pointer type solution, but it means that the typdef ends up using the type qualifiers of one of associated variables.

[mwhicks1]

Another interesting example:

typedef int * * const a;
a b;
const a c;