[LTO][PATCH] Fix another undefined reference problem.
Doug Kwan (關振德)
Fri Dec 12 21:07:00 GMT 2008
There reason why DECL_INTERFACE_KNOWN test and the assert were
removed are the original copies of constructor and destructor.
Because of multiple inheritance, the C++ FE clones any constructor or
destructor into a pair of in-charge and not-in-charge clones. The
clones are emitted but not the original. It is possible to have DECLs
of original constructor and destructor with no bodies but have
DECL_INTERFACE_SET. They also trigger the other assert. Here is some
debugging output of such a DECL.
error in foo (_ZN3fooC1Ev *INTERNAL* )
gimple_body = (nil)
CFG = (nil)
DECL_INTERFACE_KNOWN = 1
DECL_DECLARED_INLINE_P = 0
DECL_IMPLICIT_INSTANTIANTON = 0
I can put back the checks but then we need to exempt the original
constructor and destructor copies. That should be okay as they can
never cause symbol resolution problem.
2008/12/12 Diego Novillo <firstname.lastname@example.org>:
> 2008/12/11 Doug Kwan (???) <email@example.com>:
>> This patch fixes another problem where DECLs of unemitted
>> functions are written as exportable in the IL. The previous code used
>> gimple_body to check for availability of function bodies and that was
> Sorry for having missed that. I should've suggested using
> gimple_has_body_p(). This predicate will return true if the functions
> has a gimple body whether in CFG form or not.
>> +static bool
>> +cp_fix_function_decl_p (tree decl)
>> + /* Skip if DECL is not externally. */
> s/externally/externally visible/
>> + if (!TREE_PUBLIC (decl))
>> + return false;
>> + /* We need to fix DECL if it a appears to be exported but with no
>> + function body. Thunks do not have CFGs and we may need to
>> + handle them specially later. */
>> + if ((!DECL_STRUCT_FUNCTION (decl)
>> + || !DECL_STRUCT_FUNCTION (decl)->cfg)
> has_gimple_body_p (decl)
>> - /* This should only happen for inlines or implicit instanitations
>> - which are not emitted. When we reach here, we should have read
>> - the EOF and expanded all needed functions. */
>> - gcc_assert ((DECL_DECLARED_INLINE_P (t)
>> - || DECL_IMPLICIT_INSTANTIATION (t))
>> - && at_eof);
> Why are you removing this assertion? Also, why is it not necessary to check
> for DECL_INTERFACE_KNOWN anymore?
> Thanks. Diego.
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