https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125371
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
That patch is insufficient but with a bigger patch that I'm testing now, I get
this for the original example:
ss.cc: In function 'int main()':
ss.cc:5:14: error: 'istringstream' is not a member of 'std'
5 | std::istringstream foo(line);
| ^~~~~~~~~~~~~
ss.cc:2:1: note: 'std::istringstream' is defined in header '<sstream>'; this is
probably fixable by adding '#include <sstream>'
1 | #include <fstream>
+++ |+#include <sstream>
2 |
