http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60906
Sriraman Tallam <tmsriram at google dot com> changed:
What |Removed |Added
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CC| |tmsriram at google dot com
--- Comment #4 from Sriraman Tallam <tmsriram at google dot com> ---
(In reply to Harald van Dijk from comment #3)
> Speaking only as a user, the behaviour I personally naïvely expected would
> be to push the default function's attributes into each target-specific
> function's attributes, and use the already existing rules for diagnosing
> conflicting attributes. The dispatcher (ifunc) would take the attributes of
> the default function.
>
> Test cases:
>
> void f1() __attribute__((target("default")));
> void f1() __attribute__((target("arch=corei7"), noreturn));
> // valid, but would apply noreturn attribute only to arch=corei7 declaration
>
> void f2() __attribute__((target("default"), noreturn));
> void f2() __attribute__((target("arch=corei7")));
> // valid, would apply noreturn attribute to all three declarations
I do not understand why the default function's attributes should be applied to
all declarations?
>
> void f3() __attribute__((target("default"), regparm(3)));
> void f3() __attribute__((target("arch=corei7")));
> // valid, would apply regparm(3) attribute to all three declarations
>
> void f4() __attribute__((target("default")));
> void f4() __attribute__((target("arch=corei7"), regparm(3)));
> // invalid
>
> The f4 testcase would be analogous to
>
> int f(int x);
> int f(int x) __attribute__((regparm(3)));
>
> which is already a compile-time error (in 32-bit mode).
Nice list of examples. I think we can allow the various versions to have
distinct non-target attributes, I also think there is no need to apply the
default's functions attributes to all versions. Also, we should check if the
non-common attributes pose a risk like regparm and issue an error
appropriately. Then, apply only the common attributes to ifunc.
