Index: docs/LangRef.rst =================================================================== --- docs/LangRef.rst +++ docs/LangRef.rst @@ -7009,7 +7009,12 @@ to ensure that the alignment information is correct. Overestimating the alignment results in undefined behavior. Underestimating the alignment may produce less efficient code. An alignment of 1 is always safe. The -maximum possible alignment is ``1 << 29``. +maximum possible alignment is ``1 << 29``. An alignment value higher +than the size of the loaded type implies memory up to the alignment +value bytes can be safely loaded without trapping in the default +address space. Access of the high bytes can interfere with debugging +tools, so should not be accessed if the function has the +``sanitize_thread`` or ``sanitize_address`` attributes. The optional ``!nontemporal`` metadata must reference a single metadata name ```` corresponding to a metadata node with one @@ -7134,7 +7139,14 @@ to ensure that the alignment information is correct. Overestimating the alignment results in undefined behavior. Underestimating the alignment may produce less efficient code. An alignment of 1 is always -safe. The maximum possible alignment is ``1 << 29``. +safe. The maximum possible alignment is ``1 << 29``. An alignment +value higher than the size of the stored type implies memory up to the +alignment value bytes can be stored to without trapping in the default +address space. Storing to the higher bytes however may result in data +races if another thread can access the same address. Introducing a +data race is not allowed. Storing to the extra bytes is not allowed +even in situations where a data race is known to not exist if the +function has the ``sanitize_address`` attribute. The optional ``!nontemporal`` metadata must reference a single metadata name ```` corresponding to a metadata node with one ``i32`` entry of