[Bug target/57631] [patch] spurious warning for avr interrupts with asm labels

["pebbles at riseup dot net" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57631

--- Comment #4 from pebbles at riseup dot net ---
(In reply to Georg-Johann Lay from comment #3)
> Would you explain what you are trying to achieve?

For one thing, I'm coding in C++, so the handlers may be mangled to the wrong
symbols unless I tell the compiler what to name them.  The warning is
misleading at least in this case.

In C++ it's conventional to place symbols inside namespaces or classes over
prefixing them with underscores.  I'm writing a library and would like users to
be able to define the handlers with names and scopes that match the style
conventions of the project.

The __ prefix generally indicates that a symbol should not be used by a library
user, and I'm trying to indicate the opposite.

> You can name the function __vectorFOO or __vector_my_ISR_function or
> whatever without raising a warning.

But that requires reading the source of GCC, which I have begun doing but is
usually not a prerequisite for coding.  The warning should tell me that
straight out.