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[RFA]: Handle multi-line versions of multi-breakpoints
- From: dje at google dot com (Doug Evans)
- To: gdb-patches at sourceware dot org
- Date: Sun, 1 Mar 2009 22:53:01 -0800 (PST)
- Subject: [RFA]: Handle multi-line versions of multi-breakpoints
Hi.
"multi-breakpoints" (multiple breakpoints for the same source line)
don't work for constructors and inline functions where the source expression
spans several lines (at least for the new testcases included in this patch).
This patch fixes it by, if there's no exact match,
rescanning the symtabs for all matches of the best match.
Included are updated testcases to exercise the bug.
The bug isn't exposed by templates, but I updated mb-templates.{cc,exp}
anyway (if only to confirm things work there too).
Ok to check in?
2009-03-01 Doug Evans <dje@google.com>
* symtab.c (expand_line_sal): If we don't find an exact match,
rescan all symtabs again to find all copies of the best match.
* gdb.cp/mb-ctor.exp: Add multi-line source statement test.
* gdb.cp/mb-ctor.cc: Ditto.
* gdb.cp/mb-inline.exp: Add multi-line source statement test.
* gdb.cp/mb-inline.h (multi_line_foo): New function.
* gdb.cp/mb-inline1.cc: Call it.
* gdb.cp/mb-inline2.cc: Ditto.
* gdb.cp/mb-templates.exp: Add multi-line source statement test.
* gdb.cp/mb-templates.cc (multi_line_foo): New template.
Index: symtab.c
===================================================================
RCS file: /cvs/src/src/gdb/symtab.c,v
retrieving revision 1.204
diff -u -p -r1.204 symtab.c
--- symtab.c 2 Mar 2009 06:33:24 -0000 1.204
+++ symtab.c 2 Mar 2009 06:39:17 -0000
@@ -4481,7 +4481,6 @@ expand_line_sal (struct symtab_and_line
else
{
struct linetable_entry *best_item = 0;
- struct symtab *best_symtab = 0;
int exact = 0;
lineno = sal.line;
@@ -4533,13 +4532,41 @@ expand_line_sal (struct symtab_and_line
&& (best_item == NULL || item->line < best_item->line))
{
best_item = item;
- best_symtab = symtab;
}
}
}
}
+
if (!exact && best_item)
- append_expanded_sal (&ret, best_symtab, lineno, best_item->pc);
+ {
+ /* We found a "good enough" match.
+ Rescan to find all such matches.
+ This is to handle constructors, templates, inline-functions
+ that have multiple breakpoints for one line number. */
+
+ ALL_SYMTABS (objfile, symtab)
+ {
+ if (strcmp (sal.symtab->filename,
+ symtab->filename) == 0)
+ {
+ struct linetable *l;
+ int len;
+ l = LINETABLE (symtab);
+ if (!l)
+ continue;
+ len = l->nitems;
+
+ for (j = 0; j < len; j++)
+ {
+ struct linetable_entry *item = &(l->item[j]);
+
+ if (item->line == best_item->line)
+ append_expanded_sal (&ret, symtab, item->line,
+ item->pc);
+ }
+ }
+ }
+ }
}
/* For optimized code, compiler can scatter one source line accross
Index: testsuite/gdb.cp/mb-ctor.cc
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-ctor.cc,v
retrieving revision 1.1
diff -u -p -r1.1 mb-ctor.cc
--- testsuite/gdb.cp/mb-ctor.cc 24 Sep 2007 07:40:32 -0000 1.1
+++ testsuite/gdb.cp/mb-ctor.cc 2 Mar 2009 06:39:17 -0000
@@ -28,11 +28,19 @@ public:
~Derived();
private:
int i;
+ int i2;
};
Derived::Derived(int i) : Base(i)
{
this->i = i;
+ /* The next statement is spread over two lines on purpose to exercise
+ a bug where breakpoints set on all but the last line of a statement
+ would not get multiple breakpoints.
+ The second line's text for gdb_get_line_number is a subset of the
+ first line so that we don't care which line gdb prints when it stops. */
+ this->i2 = // set breakpoint here
+ i; // breakpoint here
}
Derived::~Derived()
Index: testsuite/gdb.cp/mb-ctor.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-ctor.exp,v
retrieving revision 1.5
diff -u -p -r1.5 mb-ctor.exp
--- testsuite/gdb.cp/mb-ctor.exp 3 Jan 2009 05:58:04 -0000 1.5
+++ testsuite/gdb.cp/mb-ctor.exp 2 Mar 2009 06:39:17 -0000
@@ -43,6 +43,11 @@ gdb_start
gdb_reinitialize_dir $srcdir/$subdir
gdb_load ${binfile}
+if ![runto_main] then {
+ perror "couldn't run to breakpoint"
+ continue
+}
+
# Set a breakpoint with multiple locations
# and a condition.
@@ -50,34 +55,31 @@ gdb_test "break 'Derived::Derived(int)'"
"Breakpoint.*at.* file .*$srcfile, line.*\\(2 locations\\).*" \
"set-breakpoint at ctor"
+gdb_breakpoint [gdb_get_line_number "set breakpoint here"]
+
gdb_test "break 'Derived::~Derived()'" \
"Breakpoint.*at.* file .*$srcfile, line.*\\(2 locations\\).*" \
"set-breakpoint at dtor"
-gdb_run_cmd
-gdb_expect {
- -re "Breakpoint \[0-9\]+,.*Derived.*i=7.*$gdb_prompt $" {
- pass "run to breakpoint"
- }
- -re "$gdb_prompt $" {
- fail "run to breakpoint"
- }
- timeout {
- fail "run to breakpoint (timeout)"
- }
-}
+gdb_test "continue" \
+ ".*Breakpoint.*Derived.*i=7.*" \
+ "run to breakpoint 1 v1"
+
+gdb_continue_to_breakpoint "set breakpoint here" ".* breakpoint here"
gdb_test "continue" \
".*Breakpoint.*Derived.*i=15.*" \
- "run to breakpoint 2"
+ "run to breakpoint 1 v2"
+
+gdb_continue_to_breakpoint "set breakpoint here" ".* breakpoint here"
gdb_test "continue" \
".*Breakpoint.*~Derived.*" \
- "run to breakpoint 3"
+ "run to breakpoint 3 v1"
gdb_test "continue" \
".*Breakpoint.*~Derived.*" \
- "run to breakpoint 4"
+ "run to breakpoint 3 v2"
gdb_test "continue" \
".*exited normally.*" \
Index: testsuite/gdb.cp/mb-inline.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline.exp,v
retrieving revision 1.2
diff -u -p -r1.2 mb-inline.exp
--- testsuite/gdb.cp/mb-inline.exp 3 Jan 2009 05:58:04 -0000 1.2
+++ testsuite/gdb.cp/mb-inline.exp 2 Mar 2009 06:39:17 -0000
@@ -106,3 +106,25 @@ gdb_expect {
gdb_test "continue" \
".*Program exited normally.*" \
"continue with disabled breakpoint 1.2"
+
+# Make sure we can set a breakpoint on a source statement that spans
+# multiple lines.
+
+delete_breakpoints
+
+set bp_location [gdb_get_line_number "set multi-line breakpoint here" $hdrfile]
+
+if { ![runto_main] } {
+ fail "Can't run to main for multi_line_foo tests."
+ return 0
+}
+
+gdb_test "break $hdrfile:$bp_location" \
+ "Breakpoint.*at.* file .*$hdrfile, line.*\\(2 locations\\).*" \
+ "set multi_line_foo breakpoint"
+gdb_test "continue" \
+ ".*Breakpoint.*multi_line_foo \\(i=0\\).*" \
+ "run to multi_line_foo breakpoint 4 afn"
+gdb_test "continue" \
+ ".*Breakpoint.*multi_line_foo \\(i=1\\).*" \
+ "run to multi_line_foo breakpoint 4 bfn"
Index: testsuite/gdb.cp/mb-inline.h
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline.h,v
retrieving revision 1.2
diff -u -p -r1.2 mb-inline.h
--- testsuite/gdb.cp/mb-inline.h 3 Jan 2009 05:58:04 -0000 1.2
+++ testsuite/gdb.cp/mb-inline.h 2 Mar 2009 06:39:17 -0000
@@ -26,5 +26,12 @@ foo (int i)
return i; // set breakpoint here
}
+static int
+multi_line_foo (int i)
+{
+ return // set multi-line breakpoint here
+ i;
+}
+
extern int afn ();
extern int bfn ();
Index: testsuite/gdb.cp/mb-inline1.cc
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline1.cc,v
retrieving revision 1.2
diff -u -p -r1.2 mb-inline1.cc
--- testsuite/gdb.cp/mb-inline1.cc 3 Jan 2009 05:58:04 -0000 1.2
+++ testsuite/gdb.cp/mb-inline1.cc 2 Mar 2009 06:39:17 -0000
@@ -23,7 +23,7 @@
int
afn ()
{
- return foo (0);
+ return foo (0) + multi_line_foo (0);
}
int
Index: testsuite/gdb.cp/mb-inline2.cc
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline2.cc,v
retrieving revision 1.2
diff -u -p -r1.2 mb-inline2.cc
--- testsuite/gdb.cp/mb-inline2.cc 3 Jan 2009 05:58:04 -0000 1.2
+++ testsuite/gdb.cp/mb-inline2.cc 2 Mar 2009 06:39:17 -0000
@@ -21,5 +21,5 @@
int
bfn ()
{
- return foo (1);
+ return foo (1) + multi_line_foo (1);
}
Index: testsuite/gdb.cp/mb-templates.cc
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-templates.cc,v
retrieving revision 1.1
diff -u -p -r1.1 mb-templates.cc
--- testsuite/gdb.cp/mb-templates.cc 24 Sep 2007 07:40:32 -0000 1.1
+++ testsuite/gdb.cp/mb-templates.cc 2 Mar 2009 06:39:17 -0000
@@ -8,6 +8,13 @@ void foo(T i)
std::cout << "hi\n"; // set breakpoint here
}
+template<class T>
+void multi_line_foo(T i)
+{
+ std::cout // set multi-line breakpoint here
+ << "hi\n";
+}
+
int main()
{
foo<int>(0);
@@ -16,4 +23,9 @@ int main()
foo<double>(1);
foo<int>(2);
foo<double>(2);
+
+ multi_line_foo<int>(0);
+ multi_line_foo<double>(0);
+
+ return 0;
}
Index: testsuite/gdb.cp/mb-templates.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-templates.exp,v
retrieving revision 1.5
diff -u -p -r1.5 mb-templates.exp
--- testsuite/gdb.cp/mb-templates.exp 3 Jan 2009 05:58:04 -0000 1.5
+++ testsuite/gdb.cp/mb-templates.exp 2 Mar 2009 06:39:17 -0000
@@ -165,3 +165,25 @@ gdb_test "continue" \
".*Breakpoint.*foo<int> \\(i=1\\).*" \
"instantiation: run to breakpoint 2"
+
+# Make sure we can set a breakpoint on a source statement that spans
+# multiple lines.
+
+delete_breakpoints
+
+set bp_location [gdb_get_line_number "set multi-line breakpoint here"]
+
+if { ![runto_main] } {
+ fail "Can't run to main for multi_line_foo tests."
+ return 0
+}
+
+gdb_test "break $srcfile:$bp_location" \
+ "Breakpoint.*at.* file .*$srcfile, line.*\\(2 locations\\).*" \
+ "set multi_line_foo breakpoint"
+gdb_test "continue" \
+ ".*Breakpoint.*multi_line_foo<int> \\(i=0\\).*" \
+ "run to multi_line_foo breakpoint 2 <int>"
+gdb_test "continue" \
+ ".*Breakpoint.*multi_line_foo<double> \\(i=0\\).*" \
+ "run to multi_line_foo breakpoint 2 <double>"