PR 68496 points out a bug in the handling of reflect.Call calling a function that returns a zero-sized type. libffi doesn't understand zero-sized types, which don't exist in C, so they require special handling. This patch fixes the problem. Bootstrapped and ran Go testsuite on x86_64-pc-linux-gnu. Committed to mainline and GCC 5 branch.
Ian
Index: gcc/go/gofrontend/MERGE =================================================================== --- gcc/go/gofrontend/MERGE (revision 230759) +++ gcc/go/gofrontend/MERGE (working copy) @@ -1,4 +1,4 @@ -97ec885c715b3922b0866c081554899b8d50933a +0d979f0b860cfd879754150e0ae5e1018b94d7c4 The first line of this file holds the git revision number of the last merge done from the gofrontend repository. Index: libgo/runtime/go-reflect-call.c =================================================================== --- libgo/runtime/go-reflect-call.c (revision 230759) +++ libgo/runtime/go-reflect-call.c (working copy) @@ -81,6 +81,12 @@ go_results_size (const struct __go_func_ off = (off + maxalign - 1) & ~ (maxalign - 1); + // The libffi library doesn't understand a struct with no fields. + // We generate a struct with a single field of type void. When used + // as a return value, libffi will think that requires a byte. + if (off == 0) + off = 1; + return off; }
