[gouarin]

Checklist

• The title and commit message(s) are descriptive.
• Small commits made to fix your PR have been squashed to avoid history pollution.
• Tests have been added for new features or bug fixes.
• API of new functions and classes are documented (no public API changes).

Description

Both overloads of xoptional_assembly_storage::data() contained pointer(front()); without return. C++ parses that statement as the declaration of a local function named front, so the functions fall off the end without returning a value:

auto stor = xt::optional_assembly_storage(v, f);
stor.data()->value();  // undefined behavior, segfaults with GCC 15 at -O2

Calling both overloads in the same translation unit does not compile either, because the two local declarations of front have different return types. GCC reports the statement with -Wparentheses and -Wshadow.

data() now returns the closure pointer to the front element. xoptional_assembly_storage.data checks the mutable and const overloads; it does not compile on master and passes with the fix.

[codspeed]

Merging this PR will not alter performance

1 warning

⚠️ Unable to measure the execution of 1 benchmark

This benchmark measured no execution time, so its result is not comparable and counts as unchanged. This usually happens when the compiler removes the code under test.

Prevent compiler optimizations

See affected benchmarks

✅ 255 untouched benchmarks

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_{Comparing gouarin:fix-optional-storage-data (a938086) with master (57f3d07)}