Internal error "missing default rescan info" in CTAD with a dependent static data member

[jakub-labenski]

Issue Summary

In C++17 mode, the front end hits the internal error "missing default rescan info" when it builds an implicit deduction guide for class template argument deduction
(CTAD). It happens when all of these are true:

• A constructor parameter's type is a class template specialization (e.g. P<b>).
• The specialization's nontype template argument refers to a dependent static data member (b).
• The same specialization already appears earlier in the class, for example in a member declaration.

Reproducing Source Code

template<int> struct P {};
template<typename T> struct A {
  static constexpr bool b = sizeof(T) == 1;
  P<b> m;
  A(T, P<b>);
};

void g() { A{char{}, {}}; }

Command-line Options

cpfe --c++17 test.cpp

Type of Issue

[Front End] This code SHOULD compile with these options.

Additional Details

[dev@edg workspace]$ ./build/gcc/bin/cpfe --c++17 test.cpp 
"test.cpp", line 7: internal error: assertion failed: missing default rescan
          info (exprutil.c, line 4879 in get_expr_rescan_info)

  void g() { A{char{}, {}}; }
                          ^

1 catastrophic error detected in the compilation of "test.cpp".
Compilation aborted.

Reproducing (Standard) Configuration(s)

linux-gcc-debug

Reproducing (Non-standard) Configuration

No response

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• I have checked open issues and existing discussions before filing this report.
• The reproducing source code that I have provided does not depend on headers that I have not included with my submission.
• I have reduced the reproducing source code to the best of my ability.
• I have selected at least one standard configuration or uploaded a non-standard configuration dump.
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