On Fri, 29 Nov 2019, Martin Reinecke wrote: > Hi, > > g++ is unhappy about the statement: > > template<typename T, int len> using vtype = T __attribute__ > ((vector_size (len*sizeof(T)))); > > and reports: > > vectest.cc:1:91: warning: ignoring attributes applied to dependent type > ‘T’ without an associated declaration [-Wattributes] > 1 | using vtype = T __attribute__ ((vector_size (len*sizeof(T)))); > | ^ > > clang++ on the other hand seems to be OK with this. > > Is there some subtlety I'm missing? > If so, is there analternative way to express what I have in mind? gcc expects the attribute on the type being declared, not the base type, so you need to place the attribute on vtype: template<typename T, int len> using vtype __attribute__ ((vector_size (len*sizeof(T)))) = T; This matches how [[attributes]] are meant to be placed in C++11 alias templates. Alexander
