On Wed, Aug 24, 2016 at 04:03:10PM -0400, David Malcolm wrote: > I was thinking about maybe: > rich_location::add_fixit_insert_after_caret (source_location loc) > which would add it immediately after the *caret* location of loc - as > opposed to after the *finish* location of loc, or maybe just: > rich_location::add_fixit_insert_after (source_location loc) > which > would take into account the finish location of loc. > > Having a helper in rich_location for this would be good, for protecting > against cases where some of the tokens are in a macro expansion, and others > aren't (I think fix-its within a rich_location ought to be atomic: if some > can't be applied, none should be). I'd rather have the rich_location > machinery care about these awkward issues in one place, rather than force > every diagnostic to do it. Yes, sure.
> I already have the beginnings of some fixit validation code written (but not > posted), so maybe you should go ahead and post the patch as-is, and we can > move the relevant parts into a helper as a followup? Ok, how about this one? Bootstrapped/regtested on x86_64-linux, ok for trunk? 2016-08-25 Marek Polacek <pola...@redhat.com> David Malcolm <dmalc...@redhat.com> * c-common.c (warn_logical_not_parentheses): Print fixit hints. * c-common.h (warn_logical_not_parentheses): Update declaration. * c-typeck.c (parser_build_binary_op): Pass LHS to warn_logical_not_parentheses. * parser.c (cp_parser_binary_expression): Pass LHS to warn_logical_not_parentheses. * c-c++-common/Wlogical-not-parentheses-2.c: New test. diff --git gcc/c-family/c-common.c gcc/c-family/c-common.c index 3feb910..001070d 100644 --- gcc/c-family/c-common.c +++ gcc/c-family/c-common.c @@ -1485,7 +1485,7 @@ warn_tautological_cmp (location_t loc, enum tree_code code, tree lhs, tree rhs) void warn_logical_not_parentheses (location_t location, enum tree_code code, - tree rhs) + tree lhs, tree rhs) { if (TREE_CODE_CLASS (code) != tcc_comparison || TREE_TYPE (rhs) == NULL_TREE @@ -1498,9 +1498,21 @@ warn_logical_not_parentheses (location_t location, enum tree_code code, && integer_zerop (rhs)) return; - warning_at (location, OPT_Wlogical_not_parentheses, - "logical not is only applied to the left hand side of " - "comparison"); + if (warning_at (location, OPT_Wlogical_not_parentheses, + "logical not is only applied to the left hand side of " + "comparison") + && EXPR_HAS_LOCATION (lhs)) + { + location_t lhs_loc = EXPR_LOCATION (lhs); + rich_location richloc (line_table, lhs_loc); + richloc.add_fixit_insert (lhs_loc, "("); + location_t finish = get_finish (lhs_loc); + location_t next_loc + = linemap_position_for_loc_and_offset (line_table, finish, 1); + richloc.add_fixit_insert (next_loc, ")"); + inform_at_rich_loc (&richloc, "add parentheses around left hand side " + "expression to silence this warning"); + } } /* Warn if EXP contains any computations whose results are not used. diff --git gcc/c-family/c-common.h gcc/c-family/c-common.h index bc22baa..42ce969 100644 --- gcc/c-family/c-common.h +++ gcc/c-family/c-common.h @@ -847,7 +847,8 @@ extern void overflow_warning (location_t, tree); extern bool warn_if_unused_value (const_tree, location_t); extern void warn_logical_operator (location_t, enum tree_code, tree, enum tree_code, tree, enum tree_code, tree); -extern void warn_logical_not_parentheses (location_t, enum tree_code, tree); +extern void warn_logical_not_parentheses (location_t, enum tree_code, tree, + tree); extern void warn_tautological_cmp (location_t, enum tree_code, tree, tree); extern void check_main_parameter_types (tree decl); extern bool c_determine_visibility (tree); diff --git gcc/c/c-typeck.c gcc/c/c-typeck.c index bc8728a..2f8d611 100644 --- gcc/c/c-typeck.c +++ gcc/c/c-typeck.c @@ -3696,7 +3696,7 @@ parser_build_binary_op (location_t location, enum tree_code code, while (1); } if (TREE_CODE (TREE_TYPE (t)) != BOOLEAN_TYPE) - warn_logical_not_parentheses (location, code, arg2.value); + warn_logical_not_parentheses (location, code, arg1.value, arg2.value); } /* Warn about comparisons against string literals, with the exception diff --git gcc/cp/parser.c gcc/cp/parser.c index 690e928..d54cf8a 100644 --- gcc/cp/parser.c +++ gcc/cp/parser.c @@ -8922,7 +8922,7 @@ cp_parser_binary_expression (cp_parser* parser, bool cast_p, || TREE_TYPE (current.lhs) == NULL_TREE || TREE_CODE (TREE_TYPE (current.lhs)) != BOOLEAN_TYPE)) warn_logical_not_parentheses (current.loc, current.tree_type, - maybe_constant_value (rhs)); + current.lhs, maybe_constant_value (rhs)); overload = NULL; diff --git gcc/testsuite/c-c++-common/Wlogical-not-parentheses-2.c gcc/testsuite/c-c++-common/Wlogical-not-parentheses-2.c index e69de29..ba8dce8 100644 --- gcc/testsuite/c-c++-common/Wlogical-not-parentheses-2.c +++ gcc/testsuite/c-c++-common/Wlogical-not-parentheses-2.c @@ -0,0 +1,20 @@ +/* { dg-do compile } */ +/* { dg-options "-Wlogical-not-parentheses -fdiagnostics-show-caret" } */ + + /* Test fixit hints. */ + +int +foo (int aaa, int bbb) +{ + int r = 0; + r += (!aaa) == bbb; + r += !aaa == bbb; /* { dg-warning "logical not is only applied" } */ +/* { dg-begin-multiline-output "" } + r += !aaa == bbb; + ^~ + r += !aaa == bbb; + ^~~~ + ( ) + { dg-end-multiline-output "" } */ + return r; +} Marek