https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109814
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed| |2023-05-11
Known to work| |12.3.0
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
Summary|freestanding using cmath |[13/14 Regression]
|does not compile anymore |freestanding using cmath
| |does not compile anymore
Known to fail| |13.1.0, 14.0
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The new behaviour is documented at
https://gcc.gnu.org/onlinedocs/gcc-13.1.0/libstdc++/manual/manual/using.html
and
https://gcc.gnu.org/onlinedocs/gcc-13.1.0/libstdc++/manual/manual/using_dynamic_or_shared.html
and I've just added something to the release notes about it:
https://gcc.gnu.org/gcc-13/changes.html#libstdcxx
But that doesn't help anybody affected by this.
Is it just <cmath> that you're using? We could pretty easily remove the
<bits/requires_hosted.h> include from that file, and then you could include
<cmath> with -ffreestanding. But if you have a truly freestanding environment
(i.e. no libm present) then nothing in <cmath> is actually going to work.
If people are using more than just <cmath> with -ffreestanding then things get
harder. Where do we draw the line of what is part of the freestanding subset of
libstdc++? Do we just let people include everything, and it's their fault if
they create dependencies on malloc, __cxa_throw, RTTI etc.? That doesn't seem
nice.
