[[noreturn]] false positive when calling a [[noreturn]] constructor #218

^{Originally posted by ilazaric October 3, 2026}

Issue Summary

If a function marked with [[noreturn]] construct an object whose constructor is marked [[noreturn]],
this is not recognized, and an erroneous warning is emitted.

Reproducing Source Code

struct A {
  [[noreturn]] A() { throw 123; }
};

struct B {
  [[noreturn]] B() { A{}; }
};

[[noreturn]] void g() { A{}; }

Command-line Options

cpfe repro.cpp

Type of Issue

[Front End] This code SHOULD NOT warn with these options.

Additional Details

In the example, both B::B() and g() cause the warning to be emitted,
and it is clear they can't actually return because of A::A().

Compiler output:

"<source>", line 6: warning: function declared with "noreturn" does return
    [[noreturn]] B() { A{}; }
                            ^

"<source>", line 9: warning: function declared with "noreturn" does return
  [[noreturn]] void g() { A{}; }
                               ^

Godbolt: https://godbolt.org/z/nGvdedcsG

Also noting that the attribute on A::A() is not fully ignored,
if we remove the throw it warns there (as expected/correct).

Reproducing (Standard) Configuration(s)

linux-gcc-release

Reproducing (Non-standard) Configuration

No response

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