C++: Adjust implicit '__cxa_bad_cast' prototype to reality

In 2001 Subversion r40924 (Git commit 52a11cbfcf0cfb32628b6953588b6af4037ac0b6)
"IA-64 ABI Exception Handling", '__cxa_bad_cast' changed from 'void *' to
'void' return type:

    --- libstdc++-v3/libsupc++/exception_support.cc
    +++ /dev/null
    @@ -1,388 +0,0 @@
    -[...]
    -// Helpers for rtti. Although these don't return, we give them return types so
    -// that the type system is not broken.
    -extern "C" void *
    -__cxa_bad_cast ()
    -{
    -  [...]
    -}
    -[...]

    --- /dev/null
    +++ libstdc++-v3/libsupc++/unwind-cxx.h
    @@ -0,0 +1,163 @@
    +[...]
    +extern "C" void __cxa_bad_cast ();
    +[...]

    --- /dev/null
    +++ libstdc++-v3/libsupc++/eh_aux_runtime.cc
    @@ -0,0 +1,56 @@
    +[...]
    +extern "C" void
    +__cxa_bad_cast ()
    +{
    +  [...]
    +}
    +[...]

The implicit prototype in the C++ front end however wasn't likewise adjusted,
and so for nvptx we generate code for 'void *' return type:

    // BEGIN GLOBAL FUNCTION DECL: __cxa_bad_cast
    .extern .func (.param .u64 %value_out) __cxa_bad_cast;

    {
    .param .u64 %value_in;
    call (%value_in),__cxa_bad_cast;
    trap;
    // (noreturn)
    exit;
    // (noreturn)
    ld.param.u64 %r30,[%value_in];
    }

..., which is in conflict with the library code with 'void' return type:

    // BEGIN GLOBAL FUNCTION DECL: __cxa_bad_cast
    .visible .func __cxa_bad_cast;

    // BEGIN GLOBAL FUNCTION DEF: __cxa_bad_cast
    .visible .func __cxa_bad_cast
    {
    [...]
    }

..., and we thus get execution test FAIL for 'g++.dg/rtti/dyncast2.C':

    error   : Prototype doesn't match for '__cxa_bad_cast' in 'input file 7 at offset 51437', first defined in 'input file 7 at offset 51437'
    nvptx-run: cuLinkAddData failed: device kernel image is invalid (CUDA_ERROR_INVALID_SOURCE, 300)

With this patched, we get the expected:

     // BEGIN GLOBAL FUNCTION DECL: __cxa_bad_cast
    -.extern .func (.param .u64 %value_out) __cxa_bad_cast;
    +.extern .func __cxa_bad_cast;

     {
    -.param .u64 %value_in;
    -call (%value_in),__cxa_bad_cast;
    +call __cxa_bad_cast;
     trap;
     // (noreturn)
     exit;
     // (noreturn)
    -ld.param.u64 %r30,[%value_in];
     }

..., and execution test PASS.

	gcc/cp/
	* rtti.cc (throw_bad_cast): Adjust implicit '__cxa_bad_cast'
	prototype to reality.

0 files changed, 0 insertions, 0 deletions