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Re: [committed] Fix ICE for missing header fix-it hints with overlarge #line directives (PR c/84852)
On Thu, Mar 15, 2018 at 1:32 AM, Paul Hua <paul.hua.gm@gmail.com> wrote:
> Hi:
>
> The fixits-pr84852-1.c fails on mips64el target.
Hi,
It fails on aarch64/arm bare-metal cross toolchains with different message like:
ERROR: gcc.dg/fixits-pr84852-1.c: bad option "-812156810": must be
-exact, -glob, -regexp, or -- for " dg-warning 15 "incompatible
implicit declaration of built-in function 'strlen'" "" { target *-*-*
} -812156810 "
Thanks,
bin
>
> FAIL: gcc.dg/fixits-pr84852-1.c (test for excess errors)
> FAIL: gcc.dg/fixits-pr84852-1.c dg-regexp 25 not found:
> ".*fixits-pr84852.c:-812156810:25:"
>
> see this patch:
>
> diff --git a/gcc/testsuite/gcc.dg/fixits-pr84852-1.c
> b/gcc/testsuite/gcc.dg/fixits-pr84852-1.c
> index ed88434..98087ab 100644
> --- a/gcc/testsuite/gcc.dg/fixits-pr84852-1.c
> +++ b/gcc/testsuite/gcc.dg/fixits-pr84852-1.c
> @@ -22,4 +22,4 @@ int foo (void) { return strlen(""); }
> #endif
>
> /* We need this, to consume a stray line marker for the bogus line. */
> -/* { dg-regexp ".*fixits-pr84852.c:-812156810:25:" } */
> +/* { dg-regexp ".*fixits-pr84852-1.c:-812156810:25:" } */
>
> Thanks.
>
> On Wed, Mar 14, 2018 at 10:10 PM, David Malcolm <dmalcolm@redhat.com> wrote:
>> PR c/84852 reports an ICE inside diagnostic_show_locus when printing
>> a diagnostic for a source file with a #line >= 2^31:
>>
>> #line 7777777777
>> int foo (void) { return strlen(""); }
>>
>> where we're attempting to print a fix-it hint at the top of the file
>> and underline the "strlen" (two "line spans").
>>
>> The
>> #line 7777777777
>> won't fix within the 32-bit linenum_type, and is truncated from
>> 0x1cf977871
>> to
>> 0xcf977871
>> i.e. 3482810481 in decimal.
>>
>> Such a #line is reported by -pedantic and -pedantic-errors, but we
>> shouldn't ICE.
>>
>> The ICE is an assertion failure within layout::calculate_line_spans,
>> where the line spans have not been properly sorted.
>>
>> The layout_ranges are stored as int, rather than linenum_type,
>> giving line -812156815 for the error, and line 1 for the fix-it hint.
>>
>> However, line_span uses linenum_type rather than int.
>>
>> line_span::comparator compares these values as int, and hence
>> decides that (linenum_type)3482810481 aka (int)-812156815 is less
>> than line 1.
>>
>> This leads to this assertion failing in layout::calculate_line_spans:
>>
>> 1105 gcc_assert (next->m_first_line >= current->m_first_line);
>>
>> since it isn't the case that 1 >= 3482810481.
>>
>> The underlying problem is the mix of types for storing line numbers:
>> in parts of libcpp and diagnostic-show-locus.c we use linenum_type;
>> in other places (including libcpp's expanded_location) we use int.
>>
>> I looked at using linenum_type throughout, but doing so turned into
>> a large patch, so this patch fixes the ICE in a less invasive way
>> by merely using linenum_type more consistently just within
>> diagnostic-show-locus.c, and fixing line_span::comparator to properly
>> handle line numbers (and line number differences) >= 2^31, by using
>> a new helper function for linenum_type differences, computing the
>> difference using long long, and using the sign of the difference
>> (as the difference might not fit in the "int" return type imposed
>> by qsort).
>>
>> (The new testcases assume the host's "unsigned int" is 32 bits; is
>> there anything we support where that isn't the case?)
>>
>> I can self-approve the libcpp, diagnostic-show-locus.c and input.c
>> changes.
>>
>> As part of the selftests, I needed to add ASSERT_GT and ASSERT_LT
>> to selftest.h; I'm treating those parts of the patch as "obvious".
>>
>> Successfully bootstrapped and regression-tested on x86_64-pc-linux-gnu;
>> adds 14 PASS results to gcc.sum.
>>
>> Committed to trunk as r258526.
>>
>> gcc/ChangeLog:
>> PR c/84852
>> * diagnostic-show-locus.c (class layout_point): Convert m_line
>> from int to linenum_type.
>> (line_span::comparator): Use linenum "compare" function when
>> comparing line numbers.
>> (test_line_span): New function.
>> (layout_range::contains_point): Convert param "row" from int to
>> linenum_type.
>> (layout_range::intersects_line_p): Likewise.
>> (layout::will_show_line_p): Likewise.
>> (layout::print_source_line): Likewise.
>> (layout::should_print_annotation_line_p): Likewise.
>> (layout::print_annotation_line): Likewise.
>> (layout::print_leading_fixits): Likewise.
>> (layout::annotation_line_showed_range_p): Likewise.
>> (struct line_corrections): Likewise for field m_row.
>> (line_corrections::line_corrections): Likewise for param "row".
>> (layout::print_trailing_fixits): Likewise.
>> (layout::get_state_at_point): Likewise.
>> (layout::get_x_bound_for_row): Likewise.
>> (layout::print_line): Likewise.
>> (diagnostic_show_locus): Likewise for locals "last_line" and
>> "row".
>> (selftest::diagnostic_show_locus_c_tests): Call test_line_span.
>> * input.c (selftest::test_linenum_comparisons): New function.
>> (selftest::input_c_tests): Call it.
>> * selftest.c (selftest::test_assertions): Test ASSERT_GT,
>> ASSERT_GT_AT, ASSERT_LT, and ASSERT_LT_AT.
>> * selftest.h (ASSERT_GT): New macro.
>> (ASSERT_GT_AT): New macro.
>> (ASSERT_LT): New macro.
>> (ASSERT_LT_AT): New macro.
>>
>> gcc/testsuite/ChangeLog:
>> PR c/84852
>> * gcc.dg/fixits-pr84852-1.c: New test.
>> * gcc.dg/fixits-pr84852-2.c: New test.
>>
>> libcpp/ChangeLog:
>> * include/line-map.h (compare): New function on linenum_type.
>> ---
>> gcc/diagnostic-show-locus.c | 105 ++++++++++++++++++++++----------
>> gcc/input.c | 16 +++++
>> gcc/selftest.c | 4 ++
>> gcc/selftest.h | 38 ++++++++++++
>> gcc/testsuite/gcc.dg/fixits-pr84852-1.c | 25 ++++++++
>> gcc/testsuite/gcc.dg/fixits-pr84852-2.c | 25 ++++++++
>> libcpp/include/line-map.h | 12 ++++
>> 7 files changed, 192 insertions(+), 33 deletions(-)
>> create mode 100644 gcc/testsuite/gcc.dg/fixits-pr84852-1.c
>> create mode 100644 gcc/testsuite/gcc.dg/fixits-pr84852-2.c
>>
>> diff --git a/gcc/diagnostic-show-locus.c b/gcc/diagnostic-show-locus.c
>> index 5eee3cc..bdf608a 100644
>> --- a/gcc/diagnostic-show-locus.c
>> +++ b/gcc/diagnostic-show-locus.c
>> @@ -115,7 +115,7 @@ class layout_point
>> : m_line (exploc.line),
>> m_column (exploc.column) {}
>>
>> - int m_line;
>> + linenum_type m_line;
>> int m_column;
>> };
>>
>> @@ -129,8 +129,8 @@ class layout_range
>> bool show_caret_p,
>> const expanded_location *caret_exploc);
>>
>> - bool contains_point (int row, int column) const;
>> - bool intersects_line_p (int row) const;
>> + bool contains_point (linenum_type row, int column) const;
>> + bool intersects_line_p (linenum_type row) const;
>>
>> layout_point m_start;
>> layout_point m_finish;
>> @@ -172,16 +172,52 @@ struct line_span
>> {
>> const line_span *ls1 = (const line_span *)p1;
>> const line_span *ls2 = (const line_span *)p2;
>> - int first_line_diff = (int)ls1->m_first_line - (int)ls2->m_first_line;
>> - if (first_line_diff)
>> - return first_line_diff;
>> - return (int)ls1->m_last_line - (int)ls2->m_last_line;
>> + int first_line_cmp = compare (ls1->m_first_line, ls2->m_first_line);
>> + if (first_line_cmp)
>> + return first_line_cmp;
>> + return compare (ls1->m_last_line, ls2->m_last_line);
>> }
>>
>> linenum_type m_first_line;
>> linenum_type m_last_line;
>> };
>>
>> +#if CHECKING_P
>> +
>> +/* Selftests for line_span. */
>> +
>> +static void
>> +test_line_span ()
>> +{
>> + line_span line_one (1, 1);
>> + ASSERT_EQ (1, line_one.get_first_line ());
>> + ASSERT_EQ (1, line_one.get_last_line ());
>> + ASSERT_FALSE (line_one.contains_line_p (0));
>> + ASSERT_TRUE (line_one.contains_line_p (1));
>> + ASSERT_FALSE (line_one.contains_line_p (2));
>> +
>> + line_span lines_1_to_3 (1, 3);
>> + ASSERT_EQ (1, lines_1_to_3.get_first_line ());
>> + ASSERT_EQ (3, lines_1_to_3.get_last_line ());
>> + ASSERT_TRUE (lines_1_to_3.contains_line_p (1));
>> + ASSERT_TRUE (lines_1_to_3.contains_line_p (3));
>> +
>> + ASSERT_EQ (0, line_span::comparator (&line_one, &line_one));
>> + ASSERT_GT (line_span::comparator (&lines_1_to_3, &line_one), 0);
>> + ASSERT_LT (line_span::comparator (&line_one, &lines_1_to_3), 0);
>> +
>> + /* A linenum > 2^31. */
>> + const linenum_type LARGEST_LINE = 0xffffffff;
>> + line_span largest_line (LARGEST_LINE, LARGEST_LINE);
>> + ASSERT_EQ (LARGEST_LINE, largest_line.get_first_line ());
>> + ASSERT_EQ (LARGEST_LINE, largest_line.get_last_line ());
>> +
>> + ASSERT_GT (line_span::comparator (&largest_line, &line_one), 0);
>> + ASSERT_LT (line_span::comparator (&line_one, &largest_line), 0);
>> +}
>> +
>> +#endif /* #if CHECKING_P */
>> +
>> /* A class to control the overall layout when printing a diagnostic.
>>
>> The layout is determined within the constructor.
>> @@ -207,18 +243,18 @@ class layout
>>
>> expanded_location get_expanded_location (const line_span *) const;
>>
>> - void print_line (int row);
>> + void print_line (linenum_type row);
>>
>> private:
>> - bool will_show_line_p (int row) const;
>> - void print_leading_fixits (int row);
>> - void print_source_line (int row, const char *line, int line_width,
>> + bool will_show_line_p (linenum_type row) const;
>> + void print_leading_fixits (linenum_type row);
>> + void print_source_line (linenum_type row, const char *line, int line_width,
>> line_bounds *lbounds_out);
>> - bool should_print_annotation_line_p (int row) const;
>> - void print_annotation_line (int row, const line_bounds lbounds);
>> - void print_trailing_fixits (int row);
>> + bool should_print_annotation_line_p (linenum_type row) const;
>> + void print_annotation_line (linenum_type row, const line_bounds lbounds);
>> + void print_trailing_fixits (linenum_type row);
>>
>> - bool annotation_line_showed_range_p (int line, int start_column,
>> + bool annotation_line_showed_range_p (linenum_type line, int start_column,
>> int finish_column) const;
>> void show_ruler (int max_column) const;
>>
>> @@ -230,13 +266,13 @@ class layout
>>
>> bool
>> get_state_at_point (/* Inputs. */
>> - int row, int column,
>> + linenum_type row, int column,
>> int first_non_ws, int last_non_ws,
>> /* Outputs. */
>> point_state *out_state);
>>
>> int
>> - get_x_bound_for_row (int row, int caret_column,
>> + get_x_bound_for_row (linenum_type row, int caret_column,
>> int last_non_ws);
>>
>> void
>> @@ -417,7 +453,7 @@ layout_range::layout_range (const expanded_location *start_exploc,
>> - 'a' indicates a subsequent point *after* the range. */
>>
>> bool
>> -layout_range::contains_point (int row, int column) const
>> +layout_range::contains_point (linenum_type row, int column) const
>> {
>> gcc_assert (m_start.m_line <= m_finish.m_line);
>> /* ...but the equivalent isn't true for the columns;
>> @@ -478,7 +514,7 @@ layout_range::contains_point (int row, int column) const
>> /* Does this layout_range contain any part of line ROW? */
>>
>> bool
>> -layout_range::intersects_line_p (int row) const
>> +layout_range::intersects_line_p (linenum_type row) const
>> {
>> gcc_assert (m_start.m_line <= m_finish.m_line);
>> if (row < m_start.m_line)
>> @@ -940,7 +976,7 @@ layout::maybe_add_location_range (const location_range *loc_range,
>> /* Return true iff ROW is within one of the line spans for this layout. */
>>
>> bool
>> -layout::will_show_line_p (int row) const
>> +layout::will_show_line_p (linenum_type row) const
>> {
>> for (int line_span_idx = 0; line_span_idx < get_num_line_spans ();
>> line_span_idx++)
>> @@ -1138,7 +1174,7 @@ layout::calculate_line_spans ()
>> is its width. */
>>
>> void
>> -layout::print_source_line (int row, const char *line, int line_width,
>> +layout::print_source_line (linenum_type row, const char *line, int line_width,
>> line_bounds *lbounds_out)
>> {
>> m_colorizer.set_normal_text ();
>> @@ -1201,7 +1237,7 @@ layout::print_source_line (int row, const char *line, int line_width,
>> i.e. if any of m_layout_ranges contains ROW. */
>>
>> bool
>> -layout::should_print_annotation_line_p (int row) const
>> +layout::should_print_annotation_line_p (linenum_type row) const
>> {
>> layout_range *range;
>> int i;
>> @@ -1215,7 +1251,7 @@ layout::should_print_annotation_line_p (int row) const
>> source line. */
>>
>> void
>> -layout::print_annotation_line (int row, const line_bounds lbounds)
>> +layout::print_annotation_line (linenum_type row, const line_bounds lbounds)
>> {
>> int x_bound = get_x_bound_for_row (row, m_exploc.column,
>> lbounds.m_last_non_ws);
>> @@ -1263,7 +1299,7 @@ layout::print_annotation_line (int row, const line_bounds lbounds)
>> itself, with a leading '+'. */
>>
>> void
>> -layout::print_leading_fixits (int row)
>> +layout::print_leading_fixits (linenum_type row)
>> {
>> for (unsigned int i = 0; i < m_fixit_hints.length (); i++)
>> {
>> @@ -1301,7 +1337,7 @@ layout::print_leading_fixits (int row)
>> the exact range from START_COLUMN to FINISH_COLUMN. */
>>
>> bool
>> -layout::annotation_line_showed_range_p (int line, int start_column,
>> +layout::annotation_line_showed_range_p (linenum_type line, int start_column,
>> int finish_column) const
>> {
>> layout_range *range;
>> @@ -1552,7 +1588,7 @@ correction::ensure_terminated ()
>>
>> struct line_corrections
>> {
>> - line_corrections (const char *filename, int row)
>> + line_corrections (const char *filename, linenum_type row)
>> : m_filename (filename), m_row (row)
>> {}
>> ~line_corrections ();
>> @@ -1560,7 +1596,7 @@ struct line_corrections
>> void add_hint (const fixit_hint *hint);
>>
>> const char *m_filename;
>> - int m_row;
>> + linenum_type m_row;
>> auto_vec <correction *> m_corrections;
>> };
>>
>> @@ -1674,7 +1710,7 @@ line_corrections::add_hint (const fixit_hint *hint)
>> in layout::print_leading_fixits. */
>>
>> void
>> -layout::print_trailing_fixits (int row)
>> +layout::print_trailing_fixits (linenum_type row)
>> {
>> /* Build a list of correction instances for the line,
>> potentially consolidating hints (for the sake of readability). */
>> @@ -1761,7 +1797,7 @@ layout::print_newline ()
>>
>> bool
>> layout::get_state_at_point (/* Inputs. */
>> - int row, int column,
>> + linenum_type row, int column,
>> int first_non_ws, int last_non_ws,
>> /* Outputs. */
>> point_state *out_state)
>> @@ -1806,7 +1842,7 @@ layout::get_state_at_point (/* Inputs. */
>> character of source (as determined when printing the source line). */
>>
>> int
>> -layout::get_x_bound_for_row (int row, int caret_column,
>> +layout::get_x_bound_for_row (linenum_type row, int caret_column,
>> int last_non_ws_column)
>> {
>> int result = caret_column + 1;
>> @@ -1897,7 +1933,7 @@ layout::show_ruler (int max_column) const
>> consisting of any caret/underlines, then any fixits.
>> If the source line can't be read, print nothing. */
>> void
>> -layout::print_line (int row)
>> +layout::print_line (linenum_type row)
>> {
>> int line_width;
>> const char *line = location_get_source_line (m_exploc.file, row,
>> @@ -1977,8 +2013,9 @@ diagnostic_show_locus (diagnostic_context * context,
>> expanded_location exploc = layout.get_expanded_location (line_span);
>> context->start_span (context, exploc);
>> }
>> - int last_line = line_span->get_last_line ();
>> - for (int row = line_span->get_first_line (); row <= last_line; row++)
>> + linenum_type last_line = line_span->get_last_line ();
>> + for (linenum_type row = line_span->get_first_line ();
>> + row <= last_line; row++)
>> layout.print_line (row);
>> }
>>
>> @@ -3129,6 +3166,8 @@ test_fixit_deletion_affecting_newline (const line_table_case &case_)
>> void
>> diagnostic_show_locus_c_tests ()
>> {
>> + test_line_span ();
>> +
>> test_layout_range_for_single_point ();
>> test_layout_range_for_single_line ();
>> test_layout_range_for_multiple_lines ();
>> diff --git a/gcc/input.c b/gcc/input.c
>> index 081e785..b667576 100644
>> --- a/gcc/input.c
>> +++ b/gcc/input.c
>> @@ -1595,6 +1595,21 @@ get_num_source_ranges_for_substring (cpp_reader *pfile,
>>
>> /* Selftests of location handling. */
>>
>> +/* Verify that compare() on linenum_type handles comparisons over the full
>> + range of the type. */
>> +
>> +static void
>> +test_linenum_comparisons ()
>> +{
>> + linenum_type min_line (0);
>> + linenum_type max_line (0xffffffff);
>> + ASSERT_EQ (0, compare (min_line, min_line));
>> + ASSERT_EQ (0, compare (max_line, max_line));
>> +
>> + ASSERT_GT (compare (max_line, min_line), 0);
>> + ASSERT_LT (compare (min_line, max_line), 0);
>> +}
>> +
>> /* Helper function for verifying location data: when location_t
>> values are > LINE_MAP_MAX_LOCATION_WITH_COLS, they are treated
>> as having column 0. */
>> @@ -3528,6 +3543,7 @@ for_each_line_table_case (void (*testcase) (const line_table_case &))
>> void
>> input_c_tests ()
>> {
>> + test_linenum_comparisons ();
>> test_should_have_column_data_p ();
>> test_unknown_location ();
>> test_builtins ();
>> diff --git a/gcc/selftest.c b/gcc/selftest.c
>> index 0f6c5e4..5709110 100644
>> --- a/gcc/selftest.c
>> +++ b/gcc/selftest.c
>> @@ -288,6 +288,10 @@ test_assertions ()
>> ASSERT_EQ (1, 1);
>> ASSERT_EQ_AT (SELFTEST_LOCATION, 1, 1);
>> ASSERT_NE (1, 2);
>> + ASSERT_GT (2, 1);
>> + ASSERT_GT_AT (SELFTEST_LOCATION, 2, 1);
>> + ASSERT_LT (1, 2);
>> + ASSERT_LT_AT (SELFTEST_LOCATION, 1, 2);
>> ASSERT_STREQ ("test", "test");
>> ASSERT_STREQ_AT (SELFTEST_LOCATION, "test", "test");
>> ASSERT_STR_CONTAINS ("foo bar baz", "bar");
>> diff --git a/gcc/selftest.h b/gcc/selftest.h
>> index 67d55eb..e3117c6 100644
>> --- a/gcc/selftest.h
>> +++ b/gcc/selftest.h
>> @@ -333,6 +333,44 @@ extern int num_passes;
>> ::selftest::fail ((LOC), desc); \
>> SELFTEST_END_STMT
>>
>> +/* Evaluate LHS and RHS and compare them with >, calling
>> + ::selftest::pass if LHS > RHS,
>> + ::selftest::fail otherwise. */
>> +
>> +#define ASSERT_GT(LHS, RHS) \
>> + ASSERT_GT_AT ((SELFTEST_LOCATION), (LHS), (RHS))
>> +
>> +/* Like ASSERT_GT, but treat LOC as the effective location of the
>> + selftest. */
>> +
>> +#define ASSERT_GT_AT(LOC, LHS, RHS) \
>> + SELFTEST_BEGIN_STMT \
>> + const char *desc_ = "ASSERT_GT (" #LHS ", " #RHS ")"; \
>> + if ((LHS) > (RHS)) \
>> + ::selftest::pass ((LOC), desc_); \
>> + else \
>> + ::selftest::fail ((LOC), desc_); \
>> + SELFTEST_END_STMT
>> +
>> +/* Evaluate LHS and RHS and compare them with <, calling
>> + ::selftest::pass if LHS < RHS,
>> + ::selftest::fail otherwise. */
>> +
>> +#define ASSERT_LT(LHS, RHS) \
>> + ASSERT_LT_AT ((SELFTEST_LOCATION), (LHS), (RHS))
>> +
>> +/* Like ASSERT_LT, but treat LOC as the effective location of the
>> + selftest. */
>> +
>> +#define ASSERT_LT_AT(LOC, LHS, RHS) \
>> + SELFTEST_BEGIN_STMT \
>> + const char *desc_ = "ASSERT_LT (" #LHS ", " #RHS ")"; \
>> + if ((LHS) < (RHS)) \
>> + ::selftest::pass ((LOC), desc_); \
>> + else \
>> + ::selftest::fail ((LOC), desc_); \
>> + SELFTEST_END_STMT
>> +
>> /* Evaluate EXPECTED and ACTUAL and compare them with strcmp, calling
>> ::selftest::pass if they are equal,
>> ::selftest::fail if they are non-equal. */
>> diff --git a/gcc/testsuite/gcc.dg/fixits-pr84852-1.c b/gcc/testsuite/gcc.dg/fixits-pr84852-1.c
>> new file mode 100644
>> index 0000000..ed88434
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.dg/fixits-pr84852-1.c
>> @@ -0,0 +1,25 @@
>> +/* This is padding (to avoid the output containing DejaGnu directives). */
>> +
>> +/* We need -fdiagnostics-show-caret to trigger the ICE. */
>> +
>> +/* { dg-options "-fdiagnostics-show-caret -pedantic-errors -Wno-implicit-function-declaration" } */
>> +
>> +#line 3482810481 /* { dg-error "line number out of range" } */
>> +/* { dg-begin-multiline-output "" }
>> + #line 3482810481
>> + ^~~~~~~~~~
>> + { dg-end-multiline-output "" } */
>> +
>> +int foo (void) { return strlen(""); }
>> +
>> +/* { dg-warning "incompatible implicit declaration of built-in function 'strlen'" "" { target *-*-* } -812156810 } */
>> +/* { dg-message "include '<string.h>' or provide a declaration of 'strlen'" "" { target *-*-* } -812156810 } */
>> +#if 0
>> +{ dg-begin-multiline-output "" }
>> ++#include <string.h>
>> + /* This is padding (to avoid the output containing DejaGnu directives). */
>> +{ dg-end-multiline-output "" }
>> +#endif
>> +
>> +/* We need this, to consume a stray line marker for the bogus line. */
>> +/* { dg-regexp ".*fixits-pr84852.c:-812156810:25:" } */
>> diff --git a/gcc/testsuite/gcc.dg/fixits-pr84852-2.c b/gcc/testsuite/gcc.dg/fixits-pr84852-2.c
>> new file mode 100644
>> index 0000000..0674ef5
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.dg/fixits-pr84852-2.c
>> @@ -0,0 +1,25 @@
>> +/* This is padding (to avoid the output containing DejaGnu directives). */
>> +
>> +/* We need -fdiagnostics-show-caret to trigger the ICE. */
>> +
>> +/* { dg-options "-fdiagnostics-show-caret -pedantic-errors -Wno-implicit-function-declaration" } */
>> +
>> +#line 7777777777 /* { dg-error "line number out of range" } */
>> +/* { dg-begin-multiline-output "" }
>> + #line 7777777777
>> + ^~~~~~~~~~
>> + { dg-end-multiline-output "" } */
>> +
>> +int foo (void) { return strlen(""); }
>> +
>> +/* { dg-warning "incompatible implicit declaration of built-in function 'strlen'" "" { target *-*-* } -812156810 } */
>> +/* { dg-message "include '<string.h>' or provide a declaration of 'strlen'" "" { target *-*-* } -812156810 } */
>> +#if 0
>> +{ dg-begin-multiline-output "" }
>> ++#include <string.h>
>> + /* This is padding (to avoid the output containing DejaGnu directives). */
>> +{ dg-end-multiline-output "" }
>> +#endif
>> +
>> +/* We need this, to consume a stray line marker for the bogus line. */
>> +/* { dg-regexp ".*fixits-pr84852-2.c:-812156810:25:" } */
>> diff --git a/libcpp/include/line-map.h b/libcpp/include/line-map.h
>> index f6242fc..d6cf816 100644
>> --- a/libcpp/include/line-map.h
>> +++ b/libcpp/include/line-map.h
>> @@ -49,6 +49,18 @@ along with this program; see the file COPYING3. If not see
>> /* The type of line numbers. */
>> typedef unsigned int linenum_type;
>>
>> +/* A function for for use by qsort for comparing line numbers. */
>> +
>> +inline int compare (linenum_type lhs, linenum_type rhs)
>> +{
>> + /* Avoid truncation issues by using long long for the comparison,
>> + and only consider the sign of the result. */
>> + long long diff = (long long)lhs - (long long)rhs;
>> + if (diff)
>> + return diff > 0 ? 1 : -1;
>> + return 0;
>> +}
>> +
>> /* Reason for creating a new line map with linemap_add. LC_ENTER is
>> when including a new file, e.g. a #include directive in C.
>> LC_LEAVE is when reaching a file's end. LC_RENAME is when a file
>> --
>> 1.8.5.3
>>