diff options
Diffstat (limited to 'gcc/c/c-decl.c')
| -rw-r--r-- | gcc/c/c-decl.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c index efdf902..efb978b 100644 --- a/gcc/c/c-decl.c +++ b/gcc/c/c-decl.c @@ -7525,12 +7525,23 @@ detect_field_duplicates (tree fieldlist) /* Finish up struct info used by -Wc++-compat. */ static void -warn_cxx_compat_finish_struct (tree fieldlist) +warn_cxx_compat_finish_struct (tree fieldlist, enum tree_code code, + location_t record_loc) { unsigned int ix; tree x; struct c_binding *b; + if (fieldlist == NULL_TREE) + { + if (code == RECORD_TYPE) + warning_at (record_loc, OPT_Wc___compat, + "empty struct has size 0 in C, size 1 in C++"); + else + warning_at (record_loc, OPT_Wc___compat, + "empty union has size 0 in C, size 1 in C++"); + } + /* Set the C_TYPE_DEFINED_IN_STRUCT flag for each type defined in the current struct. We do this now at the end of the struct because the flag is used to issue visibility warnings, and we @@ -7863,7 +7874,7 @@ finish_struct (location_t loc, tree t, tree fieldlist, tree attributes, DECL_EXPR, build_decl (loc, TYPE_DECL, NULL, t))); if (warn_cxx_compat) - warn_cxx_compat_finish_struct (fieldlist); + warn_cxx_compat_finish_struct (fieldlist, TREE_CODE (t), loc); struct_parse_info->struct_types.release (); struct_parse_info->fields.release (); |