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 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 = _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
