Miro Hrončok wrote: > https://gcc.gnu.org/gcc-10/porting_to.html#common > > "Default to -fno-common > > A common mistake in C is omitting extern when declaring a global variable > in a header file. If the header is included by several files it results in > multiple definitions of the same variable. In previous GCC versions this > error is ignored. GCC 10 defaults to -fno-common, which means a linker > error will now be reported. To fix this, use extern in header files when > declaring global variables, and ensure each global is defined in exactly > one C file. As a workaround, legacy C code can be compiled with -fcommon. > > > int x; // tentative definition - avoid in header files > > extern int y; // correct declaration in a header file" I fail to see how this kind of incompatible change that breaks hundreds of packages (and certainly a lot more software out there) is an improvement. Kevin Kofler _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx