https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101168
Bug ID: 101168 Summary: gnu++14 complains about altivec types defined with using keyword in the same file with preprocessor macros Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: tuliom at ascii dot art.br Target Milestone: --- Step to reproduce the error: $ cat issue.cc #include <altivec.h> using vdbl = __vector double; #define BREAK 1 $ g++ -std=gnu++14 -c issue.cc issue.cc:4:15: error: expected type-specifier before numeric constant 4 | #define BREAK 1 | ^ issue.cc:4:9: note: in expansion of macro ‘BREAK’ 4 | #define BREAK 1 | ^~~~~ The error does not reproduce when using -std=c++14.