https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114968
--- Comment #13 from LIU Hao <lh_mouse at 126 dot com> ---
I am using a modified patch:
```
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 4d6b2b98761..fbd9b4dac2e 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -25799,6 +25799,24 @@ ix86_bitint_type_info (int n, struct bitint_info
*info)
return true;
}
+/* Returns modified FUNCTION_TYPE for cdtor callabi. */
+tree
+ix86_cxx_adjust_cdtor_callabi_fntype (tree fntype)
+{
+fprintf(stderr, "TARGET_64BIT = %d\n", (bool) TARGET_64BIT);
+fprintf(stderr, "TARGET_RTD = %d\n", (bool) TARGET_RTD);
+fprintf(stderr, "ix86_function_type_abi = %d\n", ix86_function_type_abi
(fntype));
+ if (TARGET_64BIT
+ || TARGET_RTD
+ || ix86_function_type_abi (fntype) != MS_ABI)
+ return fntype;
+ /* For 32-bit MS ABI add thiscall attribute. */
+ tree attribs = tree_cons (get_identifier ("thiscall"), NULL_TREE,
+ TYPE_ATTRIBUTES (fntype));
+fprintf(stderr, "__thiscall applied!\n");
+ return build_type_attribute_variant (fntype, attribs);
+}
+
/* Implement PUSH_ROUNDING. On 386, we have pushw instruction that
decrements by exactly 2 no matter what the position was, there is no pushb.
```
There is no message when compiling the testcase:
```
E:\lh_mouse\Desktop>g++ test.cc -Wall -Wextra
<built-in>: error: conflicting declaration of C function 'int
__cxxabiv1::__cxa_thread_atexit(void (*)(), void*, void*)'
test.cc:3:16: note: previous declaration 'int
__cxxabiv1::__cxa_thread_atexit(void (__attribute__((thiscall)) *)(void*),
void*, void*)'
3 | extern "C" int __cxa_thread_atexit(void (__thiscall* dtor)(void*),
void* obj, void* dso) noexcept;
| ^~~~~~~~~~~~~~~~~~~
```
So I suspect this is a wrong place to look at.. ?
