This patch adds hints to the option-not-found error in the driver,
using the Levenshtein distance implementation posted here:
"[PATCH 0/2] Levenshtein-based suggestions (v3)"
https://gcc.gnu.org/ml/gcc-patches/2015-10/msg03379.html
It splits out the identifier-based implementation into a new
spellcheck-tree.c, keeping the core in spellcheck.c, since the tree
checking code needed for IDENTIFIER_POINTER etc isn't available in
the driver.
Bootstrapped®rtested on top of the other patch kit (with nit fixes)
on x86_64-pc-linux-gnu; adds 5 PASS results to gcc.sum.
OK for trunk as a followup to that patch kit?
gcc/ChangeLog:
PR driver/67613
* Makefile.in (GCC_OBJS): Add spellcheck.o.
(OBJS): Add spellcheck-tree.o.
* gcc.c: Include "spellcheck.h".
(suggest_option): New function.
(driver::handle_unrecognized_options): Call suggest_option to
provide a hint about misspelled options.
* spellcheck.c: Update file comment.
(levenshtein_distance): Convert 4-param implementation from static
to extern scope. Remove note about unit tests from leading
comment for const char * implementation. Move tree
implementation to...
* spellcheck-tree.c: New file.
* spellcheck.h (levenshtein_distance): Add 4-param decl.
gcc/testsuite/ChangeLog:
PR driver/67613
* gcc/testsuite/gcc.dg/spellcheck-options-1.c: New file.
* gcc/testsuite/gcc.dg/spellcheck-options-2.c: New file.
---
gcc/Makefile.in | 3 +-
gcc/gcc.c | 51 ++++++++++++++++++++++++++++-
gcc/spellcheck-tree.c | 39 ++++++++++++++++++++++
gcc/spellcheck.c | 21 ++----------
gcc/spellcheck.h | 4 +++
gcc/testsuite/gcc.dg/spellcheck-options-1.c | 4 +++
gcc/testsuite/gcc.dg/spellcheck-options-2.c | 5 +++
7 files changed, 107 insertions(+), 20 deletions(-)
create mode 100644 gcc/spellcheck-tree.c
create mode 100644 gcc/testsuite/gcc.dg/spellcheck-options-1.c
create mode 100644 gcc/testsuite/gcc.dg/spellcheck-options-2.c
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index 9fb643e..a57bd40 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -1151,7 +1151,7 @@ CXX_TARGET_OBJS=@cxx_target_objs@
FORTRAN_TARGET_OBJS=@fortran_target_objs@
# Object files for gcc many-languages driver.
-GCC_OBJS = gcc.o gcc-main.o ggc-none.o
+GCC_OBJS = gcc.o gcc-main.o ggc-none.o spellcheck.o
c-family-warn = $(STRICT_WARN)
@@ -1395,6 +1395,7 @@ OBJS = \
simplify-rtx.o \
sparseset.o \
spellcheck.o \
+ spellcheck-tree.o \
sreal.o \
stack-ptr-mod.o \
statistics.o \
diff --git a/gcc/gcc.c b/gcc/gcc.c
index bbc9b23..ef0fb4e 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -42,6 +42,7 @@ compilation is specified by a string called a "spec". */
#include "opts.h"
#include "params.h"
#include "filenames.h"
+#include "spellcheck.h"
@@ -7598,6 +7599,45 @@ driver::maybe_putenv_OFFLOAD_TARGETS () const
offload_targets = NULL;
}
+/* Helper function for driver::handle_unrecognized_options.
+
+ Given an unrecognized option BAD_OPT (without the leading dash),
+ locate the closest reasonable matching option (again, without the
+ leading dash), or NULL. */
+
+static const char *
+suggest_option (const char *bad_opt)
+{
+ const cl_option *best_option = NULL;
+ edit_distance_t best_distance = MAX_EDIT_DISTANCE;
+
+ for (unsigned int i = 0; i < cl_options_count; i++)
+ {
+ edit_distance_t dist = levenshtein_distance (bad_opt,
+ cl_options[i].opt_text + 1);
+ if (dist < best_distance)
+ {
+ best_distance = dist;
+ best_option = &cl_options[i];
+ }
+ }
+
+ if (!best_option)
+ return NULL;
+
+ /* If more than half of the letters were misspelled, the suggestion is
+ likely to be meaningless. */
+ if (best_option)
+ {
+ unsigned int cutoff = MAX (strlen (bad_opt),
+ strlen (best_option->opt_text + 1)) / 2;
+ if (best_distance > cutoff)
+ return NULL;
+ }
+
+ return best_option->opt_text + 1;
+}
+
/* Reject switches that no pass was interested in. */
void
@@ -7605,7 +7645,16 @@ driver::handle_unrecognized_options () const
{
for (size_t i = 0; (int) i < n_switches; i++)
if (! switches[i].validated)
- error ("unrecognized command line option %<-%s%>", switches[i].part1);
+ {
+ const char *hint = suggest_option (switches[i].part1);
+ if (hint)
+ error ("unrecognized command line option %<-%s%>;"
+ " did you mean %<-%s%>?",
+ switches[i].part1, hint);
+ else
+ error ("unrecognized command line option %<-%s%>",
+ switches[i].part1);
+ }
}
/* Handle the various -print-* options, returning 0 if the driver
diff --git a/gcc/spellcheck-tree.c b/gcc/spellcheck-tree.c
new file mode 100644
index 0000000..d203776
--- /dev/null
+++ b/gcc/spellcheck-tree.c
@@ -0,0 +1,39 @@
+/* Find near-matches for identifiers.
+ Copyright (C) 2015 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "tree.h"
+#include "spellcheck.h"
+
+/* Calculate Levenshtein distance between two identifiers. */
+
+edit_distance_t
+levenshtein_distance (tree ident_s, tree ident_t)
+{
+ gcc_assert (TREE_CODE (ident_s) == IDENTIFIER_NODE);
+ gcc_assert (TREE_CODE (ident_t) == IDENTIFIER_NODE);
+
+ return levenshtein_distance (IDENTIFIER_POINTER (ident_s),
+ IDENTIFIER_LENGTH (ident_s),
+ IDENTIFIER_POINTER (ident_t),
+ IDENTIFIER_LENGTH (ident_t));
+}
diff --git a/gcc/spellcheck.c b/gcc/spellcheck.c
index 4d4c176..31fd22b 100644
--- a/gcc/spellcheck.c
+++ b/gcc/spellcheck.c
@@ -1,4 +1,4 @@
-/* Find near-matches for strings and identifiers.
+/* Find near-matches for strings.
Copyright (C) 2015 Free Software Foundation, Inc.
This file is part of GCC.
@@ -30,7 +30,7 @@ along with GCC; see the file COPYING3. If not see
This implementation uses the Wagner-Fischer algorithm. */
-static edit_distance_t
+edit_distance_t
levenshtein_distance (const char *s, int len_s,
const char *t, int len_t)
{
@@ -112,25 +112,10 @@ levenshtein_distance (const char *s, int len_s,
return result;
}
-/* Calculate Levenshtein distance between two nil-terminated strings.
- This exists purely for the unit tests. */
+/* Calculate Levenshtein distance between two nil-terminated strings. */
edit_distance_t
levenshtein_distance (const char *s, const char *t)
{
return levenshtein_distance (s, strlen (s), t, strlen (t));
}
-
-/* Calculate Levenshtein distance between two identifiers. */
-
-edit_distance_t
-levenshtein_distance (tree ident_s, tree ident_t)
-{
- gcc_assert (TREE_CODE (ident_s) == IDENTIFIER_NODE);
- gcc_assert (TREE_CODE (ident_t) == IDENTIFIER_NODE);
-
- return levenshtein_distance (IDENTIFIER_POINTER (ident_s),
- IDENTIFIER_LENGTH (ident_s),
- IDENTIFIER_POINTER (ident_t),
- IDENTIFIER_LENGTH (ident_t));
-}
diff --git a/gcc/spellcheck.h b/gcc/spellcheck.h
index 58355d6..673a756 100644
--- a/gcc/spellcheck.h
+++ b/gcc/spellcheck.h
@@ -24,6 +24,10 @@ typedef unsigned int edit_distance_t;
const edit_distance_t MAX_EDIT_DISTANCE = UINT_MAX;
extern edit_distance_t
+levenshtein_distance (const char *s, int len_s,
+ const char *t, int len_t);
+
+extern edit_distance_t
levenshtein_distance (const char *s, const char *t);
extern edit_distance_t
diff --git a/gcc/testsuite/gcc.dg/spellcheck-options-1.c
b/gcc/testsuite/gcc.dg/spellcheck-options-1.c
new file mode 100644
index 0000000..cd5fdca
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/spellcheck-options-1.c
@@ -0,0 +1,4 @@
+/* { dg-do compile } */
+/* { dg-options "-Wcoercion" } */
+/* { dg-error "unrecognized command line option '-Wcoercion'; did you mean
'-Wconversion'?" "" { target *-*-* } 0 } */
+
diff --git a/gcc/testsuite/gcc.dg/spellcheck-options-2.c
b/gcc/testsuite/gcc.dg/spellcheck-options-2.c
new file mode 100644
index 0000000..786266d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/spellcheck-options-2.c
@@ -0,0 +1,5 @@
+/* { dg-do compile } */
+/* { dg-options "-Wthis-should-not-get-a-hint" } */
+/* { dg-bogus "did you mean" "" { target *-*-* } 0 } */
+/* { dg-error "unrecognized command line option
'-Wthis-should-not-get-a-hint'" "" { target *-*-* } 0 } */
+
--
1.8.5.3
