This is what the new warning pointed out. I think all these are bugs. This patch has been tested on powerpc64le-unknown-linux-gnu, aarch64-linux-gnu, and x86_64-redhat-linux.
2016-07-27 Marek Polacek <pola...@redhat.com> PR c/7652 gcc/ * config/i386/i386.c (ix86_expand_args_builtin): Add break. (ix86_expand_round_builtin): Likewise. * config/rs6000/rs6000.c (altivec_expand_ld_builtin): Add break. (altivec_expand_st_builtin): Likewise. * gengtype.c (dbgprint_count_type_at): Add break. gcc/java/ * jcf-dump.c (print_constant): Add break. libgo/ * runtime/heapdump.c (dumpefacetypes): Add break. --- gcc/gcc/config/i386/i386.c +++ gcc/gcc/config/i386/i386.c @@ -40171,6 +40187,7 @@ ix86_expand_args_builtin (const struct builtin_description *d, case 5: pat = GEN_FCN (icode) (real_target, args[0].op, args[1].op, args[2].op, args[3].op, args[4].op); + break; case 6: pat = GEN_FCN (icode) (real_target, args[0].op, args[1].op, args[2].op, args[3].op, args[4].op, @@ -40545,6 +40562,7 @@ ix86_expand_round_builtin (const struct builtin_description *d, case 5: pat = GEN_FCN (icode) (target, args[0].op, args[1].op, args[2].op, args[3].op, args[4].op); + break; case 6: pat = GEN_FCN (icode) (target, args[0].op, args[1].op, args[2].op, args[3].op, args[4].op, --- gcc/gcc/config/rs6000/rs6000.c +++ gcc/gcc/config/rs6000/rs6000.c @@ -14401,6 +14401,7 @@ altivec_expand_ld_builtin (tree exp, rtx target, bool *expandedp) break; case ALTIVEC_BUILTIN_LD_INTERNAL_2di: icode = CODE_FOR_vector_altivec_load_v2di; + break; case ALTIVEC_BUILTIN_LD_INTERNAL_1ti: icode = CODE_FOR_vector_altivec_load_v1ti; break; @@ -14462,6 +14463,7 @@ altivec_expand_st_builtin (tree exp, rtx target ATTRIBUTE_UNUSED, break; case ALTIVEC_BUILTIN_ST_INTERNAL_2di: icode = CODE_FOR_vector_altivec_store_v2di; + break; case ALTIVEC_BUILTIN_ST_INTERNAL_1ti: icode = CODE_FOR_vector_altivec_store_v1ti; break; --- gcc/gcc/gengtype.c +++ gcc/gcc/gengtype.c @@ -175,6 +175,7 @@ dbgprint_count_type_at (const char *fil, int lin, const char *msg, type_p t) { case TYPE_UNDEFINED: nb_undefined++; + break; case TYPE_SCALAR: nb_scalar++; break; --- gcc/gcc/java/jcf-dump.c +++ gcc/gcc/java/jcf-dump.c @@ -926,6 +926,7 @@ print_constant (FILE *out, JCF *jcf, int index, int verbosity) if (verbosity > 0) fprintf (out, "Fieldref: %ld=", (long) JPOOL_USHORT2 (jcf, index)); print_constant (out, jcf, JPOOL_USHORT2 (jcf, index), 0); + break; case 5: case 6: case 7: --- gcc/libgo/runtime/heapdump.c +++ gcc/libgo/runtime/heapdump.c @@ -766,6 +766,7 @@ dumpefacetypes(void *obj __attribute__ ((unused)), uintptr size, const Type *typ for(i = 0; i <= size - type->__size; i += type->__size) //playgcprog(i, (uintptr*)type->gc + 1, dumpeface_callback, obj); break; + break; case TypeInfo_Chan: if(type->__size == 0) // channels may have zero-sized objects in them break; Marek