On 06/08/20 08:56 -0600, Martin Sebor via Libstdc++ wrote:
For this specific use case, I saw __istream_extract defined as an ordinary (non-template) function in a .tcc file in the patch so I thought it was out of line. If it's inline
It's overloaded. One is a function template defined inline, the other is a non-inline function defined in the library.
or if it's a template the only workaround I can think of to retain the warning is to have it make a call to (no-op) function with the attribute that is not inlined. It's too bad there is no attribute to tell the expander to avoid emitting such a function (which would be the equivalent of the idea I outlined in my second paragraph above).
That will still fail to warn because of -Wsystem-headers. Attempting to use attributes here achieves absolutely nothing for the problem scenarios I was concerned about. The only case where it helps is passing a null pointer or a pointer to a zero-sized buffer to operator>> and not optimising. All other problematic cases fail to warn, and it's those other cases where a warning would be helpful.
