https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98846
Bug ID: 98846
Summary: Spurious -Wregister warning
Product: gcc
Version: 10.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: programmerjake at gmail dot com
Target Milestone: ---
In:
https://gcc.godbolt.org/z/49xoKP
With the following code:
template <typename T = void>
int template_get_edx() {
register int edx asm("edx");
asm("movl $1234, %%edx\n\t# reg=%0" : "=r"(edx));
return edx;
}
template int template_get_edx<void>();
With: -O -Wall -std=c++17
produces:
<source>: In instantiation of 'int template_get_edx() [with T = void]':
<source>:8:37: required from here
<source>:3:18: warning: ISO C++17 does not allow 'register' storage class
specifier [-Wregister]
3 | register int edx asm("edx");
I think that warning is spurious because the `register` keyword is required for
clang to not ignore the asm("edx").
