if (DECL_ARTIFICIAL (fndecl))
return DECL_SOURCE_LOCATION (fndecl);
+ if (argnum == -1)
+ return DECL_SOURCE_LOCATION (fndecl);
+
int i;
tree param;
extern tree most_specialized_partial_spec (tree, tsubst_flags_t, bool = false);
extern tree most_constrained_function (tree);
extern void inform_num_candidates (location_t, int);
-extern void print_candidates (location_t, tree);
+
+/* Abstract base class for optionally providing extra diagnostic note(s)
+ about a candidate in calls to print_candidates. */
+
+class candidate_context
+{
+public:
+ virtual ~candidate_context () {}
+ virtual void emit_any_notes_for_candidate (tree cand_fndecl) = 0;
+};
+
+extern void print_candidates (location_t, tree,
+ candidate_context * = nullptr);
+
extern void instantiate_pending_templates (int);
extern tree tsubst_default_argument (tree, int, tree, tree,
tsubst_flags_t);
#include "tree-inline.h"
#include "escaped_string.h"
#include "contracts.h"
+#include "gcc-rich-location.h"
+#include "tree-pretty-print-markup.h"
/* Id for dumping the raw trees. */
int raw_dump_id;
error ("template declaration of %q#D", decl);
}
+/* A struct for conveniently working with the parameter types of a
+ fndecl. */
+
+struct fndecl_signature
+{
+ fndecl_signature (tree fndecl)
+ : m_fndecl (fndecl),
+ m_num_artificial_parms (num_artificial_parms_for (fndecl)),
+ m_variadic (true)
+ {
+ function_args_iterator iter;
+ tree argtype;
+ FOREACH_FUNCTION_ARGS (TREE_TYPE (fndecl), argtype, iter)
+ {
+ /* A trailing "void" type means that FNDECL is non-variadic. */
+ if (VOID_TYPE_P (argtype))
+ {
+ gcc_assert (!TREE_CHAIN (iter.next));
+ m_variadic = false;
+ break;
+ }
+ m_parm_types.safe_push (argtype);
+ }
+ gcc_assert (m_parm_types.length () >= (size_t)m_num_artificial_parms);
+ m_num_user_parms = m_parm_types.length () - m_num_artificial_parms;
+ }
+
+ /* Convert from index within DECL_ARGUMENTS to 0-based user-written
+ parameter, or -1 for "this". */
+ int
+ get_argno_from_idx (size_t idx) const
+ {
+ return static_cast<int> (idx) - m_num_artificial_parms;
+ }
+
+ location_t
+ get_argno_location (int argno) const
+ {
+ return get_fndecl_argument_location (m_fndecl, argno);
+ }
+
+ tree m_fndecl;
+ int m_num_artificial_parms;
+ auto_vec<tree> m_parm_types;
+ size_t m_num_user_parms;
+ bool m_variadic;
+};
+
+/* A rich_location subclass that highlights a given argno
+ within FNDECL_SIG using HIGHLIGHT_COLOR in the quoted source. */
+
+class parm_rich_location : public gcc_rich_location
+{
+public:
+ parm_rich_location (const fndecl_signature &fndecl_sig,
+ int argno,
+ const char *highlight_color)
+ : gcc_rich_location (fndecl_sig.get_argno_location (argno),
+ nullptr,
+ highlight_color)
+ {
+ }
+};
+
+/* A class for comparing a pair of fndecls and emitting diagnostic notes
+ about the differences between them, if they are sufficiently close. */
+
+class fndecl_comparison
+{
+public:
+ fndecl_comparison (tree decl_a,
+ tree decl_b)
+ : m_decl_a (decl_a),
+ m_decl_b (decl_b)
+ {
+ gcc_assert (TREE_CODE (decl_a) == FUNCTION_DECL);
+ gcc_assert (TREE_CODE (decl_b) == FUNCTION_DECL);
+ }
+
+ /* Attempt to emit diagnostic notes describing the differences between
+ the fndecls, when they are a sufficiently close match. */
+ void
+ maybe_emit_notes_for_close_match () const
+ {
+ /* If there's a difference in "variadicness", don't attempt to emit
+ any notes. */
+ if (m_decl_a.m_variadic != m_decl_b.m_variadic)
+ return;
+
+ auto_vec<parm_difference> differences = get_differences ();
+ if (differences.length () == 1)
+ {
+ auto_diagnostic_nesting_level sentinel;
+ print_parm_type_difference (differences[0]);
+ }
+ }
+
+private:
+ struct parm_difference
+ {
+ size_t m_parm_idx_a;
+ size_t m_parm_idx_b;
+ };
+
+ /* If we have a close match, return the differences between the two
+ fndecls. Otherwise return an empty vector. */
+ auto_vec<parm_difference>
+ get_differences () const
+ {
+ auto_vec<parm_difference> differences;
+
+ /* For now, just handle the case where the "user parm" count is
+ equal. */
+ if (m_decl_a.m_num_user_parms != m_decl_b.m_num_user_parms)
+ return differences;
+
+ /* Ideally we'd check the edit distance, and thus report on close
+ matches which are missing a param, have transposed params, etc.
+ For now, just iterate through the params, finding differences
+ elementwise. */
+
+ /* Find differences in artificial params, if they are comparable.
+ This should find e.g. const vs non-const differences in "this". */
+ if (m_decl_a.m_num_artificial_parms == m_decl_b.m_num_artificial_parms)
+ for (int parm_idx = 0;
+ parm_idx < m_decl_a.m_num_artificial_parms;
+ ++parm_idx)
+ compare (parm_idx, parm_idx, differences);
+
+ /* Find differences in user-provided params. */
+ for (size_t user_parm_idx = 0;
+ user_parm_idx < m_decl_a.m_num_user_parms;
+ ++user_parm_idx)
+ {
+ const size_t idx_a = m_decl_a.m_num_artificial_parms + user_parm_idx;
+ const size_t idx_b = m_decl_b.m_num_artificial_parms + user_parm_idx;
+ compare (idx_a, idx_b, differences);
+ }
+
+ return differences;
+ }
+
+ void
+ compare (size_t idx_a, size_t idx_b,
+ auto_vec<parm_difference> &differences) const
+ {
+ if (!same_type_p (m_decl_a.m_parm_types[idx_a],
+ m_decl_b.m_parm_types[idx_b]))
+ differences.safe_push (parm_difference {idx_a, idx_b});
+ }
+
+ void
+ print_parm_type_difference (const parm_difference &diff) const
+ {
+ const char * const highlight_a = "highlight-a";
+ pp_markup::element_quoted_type type_of_parm_a
+ (m_decl_a.m_parm_types[diff.m_parm_idx_a],
+ highlight_a);
+ const int argno_a = m_decl_a.get_argno_from_idx (diff.m_parm_idx_a);
+ parm_rich_location rich_loc_a (m_decl_a, argno_a, highlight_a);
+ inform (&rich_loc_a,
+ "parameter %P of candidate has type %e...",
+ argno_a, &type_of_parm_a);
+
+ const char * const highlight_b = "highlight-b";
+ pp_markup::element_quoted_type type_of_parm_b
+ (m_decl_b.m_parm_types[diff.m_parm_idx_b],
+ highlight_b);
+ const int argno_b = m_decl_b.get_argno_from_idx (diff.m_parm_idx_b);
+ parm_rich_location rich_loc_b (m_decl_b, argno_b, highlight_b);
+ inform (&rich_loc_b,
+ "...which does not match type %e",
+ &type_of_parm_b);
+ }
+
+ fndecl_signature m_decl_a;
+ fndecl_signature m_decl_b;
+};
+
+class decl_mismatch_context : public candidate_context
+{
+public:
+ decl_mismatch_context (tree function)
+ : m_function (function)
+ {
+ gcc_assert (TREE_CODE (function) == FUNCTION_DECL);
+ }
+
+ void
+ emit_any_notes_for_candidate (tree cand) final override
+ {
+ if (TREE_CODE (cand) == FUNCTION_DECL)
+ {
+ fndecl_comparison diff (cand, m_function);
+ diff.maybe_emit_notes_for_close_match ();
+ }
+ }
+private:
+ tree m_function;
+};
+
/* Sanity check: report error if this function FUNCTION is not
really a member of the class (CTYPE) it is supposed to belong to.
TEMPLATE_PARMS is used to specify the template parameters of a member
error_at (DECL_SOURCE_LOCATION (function),
"no declaration matches %q#D", function);
if (fns)
- print_candidates (DECL_SOURCE_LOCATION (function), fns);
+ {
+ decl_mismatch_context ctxt (function);
+ print_candidates (DECL_SOURCE_LOCATION (function), fns, &ctxt);
+ }
else if (DECL_CONV_FN_P (function))
inform (DECL_SOURCE_LOCATION (function),
"no conversion operators declared");
}
/* Print the list of candidate FNS in an error message. FNS can also
- be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
+ be a TREE_LIST of non-functions in the case of an ambiguous lookup.
+
+ If CAND_CTXT is non-null, use it for each candidate to allow for
+ additional per-candidate notes. */
void
-print_candidates (location_t error_loc, tree fns)
+print_candidates (location_t error_loc,
+ tree fns,
+ candidate_context *cand_ctxt)
{
auto_vec<tree> candidates;
flatten_candidates (fns, candidates);
{
tree cand = candidates[0];
inform (DECL_SOURCE_LOCATION (cand), "candidate is: %#qD", cand);
+ if (cand_ctxt)
+ cand_ctxt->emit_any_notes_for_candidate (cand);
}
else
{
int idx = 0;
for (tree cand : candidates)
- inform (DECL_SOURCE_LOCATION (cand), "candidate %i: %#qD",
- ++idx, cand);
+ {
+ inform (DECL_SOURCE_LOCATION (cand), "candidate %i: %#qD",
+ ++idx, cand);
+ if (cand_ctxt)
+ cand_ctxt->emit_any_notes_for_candidate (cand);
+ }
}
}
// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
// { dg-message "8: candidate 1: " "candidate 1" { target *-*-* } other_decl }
// { dg-message "8: candidate 2: " "candidate 2" { target *-*-* } close_decl }
+// { dg-message "34: parameter 3 of candidate has type 'void\\*'" "param of decl" { target *-*-* } close_decl }
+// { dg-message "43: \\.\\.\\.which does not match type 'const void\\*'" "param of defn" { target *-*-* } defn }
--- /dev/null
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, int j, int k); // { dg-line decl }
+};
+
+// Wrong "const"-ness of this:
+void foo::test (int i, int j, int k) const // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
+// { dg-message "8: parameter 'this' of candidate has type 'foo\\*'" "this of decl" { target *-*-* } decl }
+// { dg-message "6: \\.\\.\\.which does not match type 'const foo\\*'" "this of defn" { target *-*-* } defn }
--- /dev/null
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, int j, int k) const; // { dg-line decl }
+};
+
+// Wrong "const"-ness of "this":
+
+void foo::test (int i, int j, int k) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
+// { dg-message "8: parameter 'this' of candidate has type 'const foo\\*'" "this of decl" { target *-*-* } decl }
+// { dg-message "6: \\.\\.\\.which does not match type 'foo\\*'" "this of defn" { target *-*-* } defn }
--- /dev/null
+// { dg-additional-options "-fdiagnostics-show-caret" }
+
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, int j, void *ptr, int k); // { dg-line decl }
+};
+
+// Wrong "const"-ness of a param (param 3).
+void foo::test (int i, int j, const void *ptr, int k) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+/* { dg-begin-multiline-output "" }
+ void foo::test (int i, int j, const void *ptr, int k)
+ ^~~
+ { dg-end-multiline-output "" } */
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
+/* { dg-begin-multiline-output "" }
+ void test (int i, int j, void *ptr, int k);
+ ^~~~
+ { dg-end-multiline-output "" } */
+// { dg-message "34: parameter 3 of candidate has type 'void\\*'" "param of decl" { target *-*-* } decl }
+/* { dg-begin-multiline-output "" }
+ void test (int i, int j, void *ptr, int k);
+ ~~~~~~^~~
+ { dg-end-multiline-output "" } */
+// { dg-message "43: \\.\\.\\.which does not match type 'const void\\*'" "param of defn" { target *-*-* } defn }
+/* { dg-begin-multiline-output "" }
+ void foo::test (int i, int j, const void *ptr, int k)
+ ~~~~~~~~~~~~^~~
+ { dg-end-multiline-output "" } */
+
+/* { dg-begin-multiline-output "" }
+ class foo
+ ^~~
+ { dg-end-multiline-output "" } */
--- /dev/null
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ static void test (int i, int j, void *ptr, int k); // { dg-line decl }
+};
+
+// Wrong "const"-ness of a param, for static member fn (param 3).
+void foo::test (int i, int j, const void *ptr, int k) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "15: candidate is: " "candidate is" { target *-*-* } decl }
+// { dg-message "41: parameter 3 of candidate has type 'void\\*'" "param of decl" { target *-*-* } decl }
+// { dg-message "43: \\.\\.\\.which does not match type 'const void\\*'" "param of defn" { target *-*-* } defn }
--- /dev/null
+class bar;
+
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, foo *j, int k); // { dg-line decl }
+};
+
+// Missing '*' on a param (param 2).
+void foo::test (int i, foo j, int k) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
+// { dg-message "26: parameter 2 of candidate has type 'foo\\*'" "param of decl" { target *-*-* } decl }
+// { dg-message "28: \\.\\.\\.which does not match type 'foo'" "param of defn" { target *-*-* } defn }
--- /dev/null
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, int j, int k, ...); // { dg-line decl }
+};
+
+// Variadic vs non-variadic
+
+void foo::test (int i, int j, int k) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
--- /dev/null
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, int j, const char *k, ...); // { dg-line decl }
+};
+
+// Variadic vs non-variadic *and* a mismatching param
+
+void foo::test (int i, int j, int k) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
+
+// The candidate is too different from the decl for a "close match" hint:
+// { dg-bogus "parameter 3 of candidate has type" "param mismatch" { target *-*-* } decl }
--- /dev/null
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, int j, int k); // { dg-line decl }
+};
+
+// Variadic vs non-variadic
+
+void foo::test (int i, int j, int k, ...) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
--- /dev/null
+class foo // { dg-message "'class foo' defined here" }
+{
+public:
+ void test (int i, int j, int k); // { dg-line decl }
+};
+
+// Variadic vs non-variadic
+
+void foo::test (int i, int j, ...) // { dg-line defn }
+{
+}
+
+// { dg-error "6: no declaration matches" "error" { target *-*-* } defn }
+// { dg-message "8: candidate is: " "candidate is" { target *-*-* } decl }
projects / thirdparty / gcc.git / commitdiff
