https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111343
Bug ID: 111343
Summary: [SH] Including <cmath> in C++23 causes an ICE with
-m4-single-only
Product: gcc
Version: 13.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: gyrovorbis at gmail dot com
Target Milestone: ---
We recently updated from GCC12 to GCC13 in the Sega Dreamcast indie SDK,
KallistiOS, and while pretty much everything has worked fantastically, we are
encountering a pretty serious ICE when attempting to include the <cmath> header
with the -m4-single-only SH-specific flag (which treats doubles as floats),
when compiling as C++23.
The minimal program to reproduce the issue is here:
#include <cmath>
int main(int argc, char* argv[]) {
return 0;
}
We are building with: -std=c++23 -m4-single-only
Note that without the -m4-single-only flag, the ICE disappears. Note also that
without including <cmath>, with this flag, the following static assertion
fails:
static_assert(sizeof(__STDCPP_FLOAT64_T__) == 8,
"Oh god, Dreamcast broke!");
Here is a link to a repro in Compiler Explorer: https://godbolt.org/z/MrE8a47oq
I'm assuming the addition of the new C++23 <stdfloat> types is clashing with
the `-m4-single-only` flag, as it doesn't seem as though when these types are
created, there is any checking for sizeof(double) or anything target-specific:
https://github.com/gcc-mirror/gcc/blob/a7d052b3200c7928d903a0242b8cfd75d131e374/gcc/c-family/c-cppbuiltin.cc#L1265
