refactor: Add LIFETIMEBOUND / -Wdangling-gsl to Assert() #25248

Currently compiles clean, but I think it may still be useful.

Can be tested by adding an &:

diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index 5766fff92d..300c1ec60f 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -125,7 +125,7 @@ BOOST_AUTO_TEST_CASE(util_check)
 
     // Check -Wdangling-gsl does not trigger when copying the int. (It would
     // trigger on "const int&")
-    const int nine{*Assert(std::optional<int>{9})};
+    const int& nine{*Assert(std::optional<int>{9})};
     BOOST_CHECK_EQUAL(9, nine);
 }
 

Output:

test/util_tests.cpp:128:29: warning: object backing the pointer will be destroyed at the end of the full-expression [-Wdangling-gsl]
    const int& nine{*Assert(std::optional<int>{9})};
                            ^~~~~~~~~~~~~~~~~~~~~
./util/check.h:75:50: note: expanded from macro 'Assert'
#define Assert(val) inline_assertion_check<true>(val, __FILE__, __LINE__, __func__, #val)
                                                 ^~~
1 warning generated.

Concept ACK

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #25112 (util: Move error message formatting of NonFatalCheckError to cpp by MarcoFalke)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

ACK fa3ea81c3e7d962715788ab5525958a532c51414

Cherry-picked this commit onto the Erlay branch I'm testing, rebased to master, Clang 15 debug build clean, then added the reference & to provoke the error.

  CXX      test/test_bitcoin-util_tests.o
test/util_tests.cpp:128:29: error: object backing the pointer will be destroyed at the end of the full-expression [-Werror,-Wdangling-gsl]
    const int& nine{*Assert(std::optional<int>{9})};
                            ^~~~~~~~~~~~~~~~~~~~~
./util/check.h:75:50: note: expanded from macro 'Assert'
#define Assert(val) inline_assertion_check<true>(val, __FILE__, __LINE__, __func__, #val)
                                                 ^~~
1 error generated.

Edit: not sure an ACK in a review comment is picked up by the script, so copied it over to the review dialog.

cc @stickies-v

ACK fa3ea81c3e7d962715788ab5525958a532c51414

I can't think of any reason not to :)

This has been merged.