http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52288
Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |diagnostic Severity|normal |enhancement --- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-02-16 23:49:39 UTC --- (In reply to comment #0) > This code: > > int main(int argc, char** argv) { > bool b; > void* p = b ? [argc](int i){ return i; } : > [argc](int i){ return i; }; > return 0; } > > gets you this: > > s3:~/ootbc/personal/ivan$ g++ --std=c++0x foo.cc > foo.cc: In function âint main(int, char**)â: > foo.cc:5:28: error: no match for ternary âoperator?:â in âb ? {argc} : {argc}â > > which is a poor. What do you suggest instead? > Meanwhile this code: > > int main(int argc, char** argv) { > bool b; > void* p = b ? &[argc](int i){ return i; } : > &[argc](int i){ return i; }; > return 0; } > > gets you this: > > s3:~/ootbc/personal/ivan$ g++ --std=c++0x foo.cc > foo.cc: In function âint main(int, char**)â: > foo.cc:4:42: error: taking address of temporary [-fpermissive] > foo.cc:5:29: error: taking address of temporary [-fpermissive] > foo.cc:5:29: error: conditional expression between distinct pointer types > âmain(int, char**)::<lambda(int)>*â and âmain(int, char**)::<lambda(int)>*â > lacks a cast > > which is even worse. Why? It's entirely accurate, you can't take the address of a lambda, and the two types are different and incompatible so can't be used as the second and third operands of a conditional expression.