diff options
Diffstat (limited to 'gcc/c/c-typeck.c')
| -rw-r--r-- | gcc/c/c-typeck.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c index 9284bfc..741c75c 100644 --- a/gcc/c/c-typeck.c +++ b/gcc/c/c-typeck.c @@ -2277,6 +2277,33 @@ lookup_field_fuzzy (tree type, tree component) return find_closest_identifier (component, &candidates); } +/* Support function for build_component_ref's error-handling. + + Given DATUM_TYPE, and "DATUM.COMPONENT", where DATUM is *not* a + struct or union, should we suggest "DATUM->COMPONENT" as a hint? */ + +static bool +should_suggest_deref_p (tree datum_type) +{ + /* We don't do it for Objective-C, since Objective-C 2.0 dot-syntax + allows "." for ptrs; we could be handling a failed attempt + to access a property. */ + if (c_dialect_objc ()) + return false; + + /* Only suggest it for pointers... */ + if (TREE_CODE (datum_type) != POINTER_TYPE) + return false; + + /* ...to structs/unions. */ + tree underlying_type = TREE_TYPE (datum_type); + enum tree_code code = TREE_CODE (underlying_type); + if (code == RECORD_TYPE || code == UNION_TYPE) + return true; + else + return false; +} + /* Make an expression to refer to the COMPONENT field of structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. LOC is the location of the COMPONENT_REF. */ @@ -2369,6 +2396,18 @@ build_component_ref (location_t loc, tree datum, tree component) return ref; } + else if (should_suggest_deref_p (type)) + { + /* Special-case the error message for "ptr.field" for the case + where the user has confused "." vs "->". */ + rich_location richloc (line_table, loc); + /* "loc" should be the "." token. */ + richloc.add_fixit_replace (source_range::from_location (loc), "->"); + error_at_rich_loc (&richloc, + "%qE is a pointer; did you mean to use %<->%>?", + datum); + return error_mark_node; + } else if (code != ERROR_MARK) error_at (loc, "request for member %qE in something not a structure or union", |