[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 Patrick Palka changed: What|Removed |Added CC||ppalka at gcc dot gnu.org See

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 Andrew Pinski changed: What|Removed |Added CC||danakj at orodu dot net --- Comment #3

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 --- Comment #4 from danakj at orodu dot net --- Here's a repro without the std::string inside a union. It is the SSO union inside the string that causes the error. https://gcc.godbolt.org/z/T8oM8vYnq ``` #include template constexpr T fold(T

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 --- Comment #5 from danakj at orodu dot net --- As a means to work around #4 in static asserts, making your string long enough that it avoids the SSO will allow the compiler to accept it.

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 --- Comment #6 from danakj at orodu dot net --- In case it is of help, here's an even smaller repro that clang reports the error in libstdc++. For whatever reason gcc does not notice the libstdc++ bug here. https://gcc.godbolt.org/z/Phndafeoe `

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 --- Comment #7 from Jonathan Wakely --- That bug in comment 6 has already been fixed in gcc-12.3, by the last patch for PR 103295. The one in comment 4 is different, and will be fixed by Nathaniel's latest patch: https://gcc.gnu.org/pipermail/g

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 --- Comment #8 from Patrick Palka --- It seems the comment #4 testcase is still rejected on trunk after/despite r14-4334-g28adad7a32ed92?

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 --- Comment #9 from Jonathan Wakely --- Odd, I thought I'd checked it when testing r14-4334-g28adad7a32ed92. Seems like the same issue as PR 112642 though (which has a minimized version without std::string).

[Bug c++/110158] Cannot use union with std::string inside in constant expression

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110158 --- Comment #1 from Andrew Pinski --- Here is a slightly reduced testcase (for a slightly different issue still dealing with unions): ``` struct str1 { // bool a; char *var; union { char t[15]; int allocated; }; constexpr str1()