This is the mail archive of the gdb-patches@sourceware.org mailing list for the GDB project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH V4 5/6] Resolve dynamic target types of pointers.

On 13/10/2016 16:07, Yao Qi wrote:

Bernhard Heckel <bernhard.heckel@intel.com> writes:


diff --git a/gdb/c-valprint.c b/gdb/c-valprint.c
index 2cb418d..120163f 100644
--- a/gdb/c-valprint.c
+++ b/gdb/c-valprint.c
@@ -645,6 +645,28 @@ c_value_print (struct value *val, struct ui_file *stream,
        else
  	{
  	  /* normal case */
+	  if (TYPE_CODE (type) == TYPE_CODE_PTR
+	      && 1 == is_dynamic_type (type))

Use is_dynamic_type return value as bool.


+	    {
+	      CORE_ADDR addr;
+	      if (NULL != TYPE_DATA_LOCATION (TYPE_TARGET_TYPE (type)))
+		addr = value_address (val);
+	      else
+		addr = value_as_address (val);
+
+	      /* We resolve the target-type only when the
+	         pointer is associated.  */
+	      if ((addr != 0)
+		  && (0 == type_not_associated (type)))

!type_not_associated (type)


+
+
+gdb_breakpoint [gdb_get_line_number "Before pointer assignment"]
+gdb_continue_to_breakpoint "Before pointer assignment"
+gdb_test "print logp" "= \\(PTR TO -> \\( $logical \\)\\) 0x0" "print logp, not associated"
+gdb_test "print *logp" "Cannot access memory at address 0x0" "print *logp, not associated"
+gdb_test "print comp" "= \\(PTR TO -> \\( $complex \\)\\) 0x0" "print comp, not associated"
+gdb_test "print *comp" "Cannot access memory at address 0x0" "print *comp, not associated"
+gdb_test "print charp" "= \\(PTR TO -> \\( character\\*1 \\)\\) 0x0" "print charp, not associated"
+gdb_test "print *charp" "Cannot access memory at address 0x0" "print *charp, not associated"
+gdb_test "print charap" "= \\(PTR TO -> \\( character\\*3 \\)\\) 0x0" "print charap, not associated"
+gdb_test "print *charap" "Cannot access memory at address 0x0" "print *charap, not associated"
+gdb_test "print intp" "= \\(PTR TO -> \\( $int \\)\\) 0x0" "print intp, not associated"
+gdb_test "print *intp" "Cannot access memory at address 0x0" "print
*intp, not associated"

These lines are too long.


+set test "print intap, not associated"
+gdb_test_multiple "print intap" $test {
+  -re " = \\(PTR TO -> \\( $int \\(:,:\\)\\)\\) <not associated>\r\n$gdb_prompt $" {
+    pass $test
+  }
+  -re " = <not associated>\r\n$gdb_prompt $" {
+    pass $test
+  }
+}

Why do we need to different regex here?  Need to handle the differences
of different compilers?  IMO, the former looks reasonable to me.
A pointer to an array (especially to Variable Length Array, VLA) is described in Gfortran's compiled debug info 
like normal array types + associated property of an pointer.
Not sure if this is a bug in Gfortran or not? I was also thinking to make the output equal, and check if an array has pointer attributes but ..... I don't really like this approach. This would cause a lot of "if .. else" construct in the code for example: De-reference this pointer, Address operator, ... 


+gdb_test "print realp" "= \\(PTR TO -> \\( $real \\)\\) 0x0" "print realp, not associated"
+gdb_test "print *realp" "Cannot access memory at address 0x0" "print *realp, not associated"

They are too long.


+gdb_test "print \$my_var = intp" "= \\(PTR TO -> \\( $int \\)\\) 0x0"
+
+
+gdb_breakpoint [gdb_get_line_number "Before value assignment"]
+gdb_continue_to_breakpoint "Before value assignment"
+gdb_test "print *(twop)%ivla2" "= <not allocated>"
+
+
+gdb_breakpoint [gdb_get_line_number "After value assignment"]
+gdb_continue_to_breakpoint "After value assignment"
+gdb_test "print logp" "= \\(PTR TO -> \\( $logical \\)\\) $hex\( <.*>\)?"
+gdb_test "print *logp" "= \\.TRUE\\."
+gdb_test "print comp" "= \\(PTR TO -> \\( $complex \\)\\) $hex\( <.*>\)?"
+gdb_test "print *comp" "= \\(1,2\\)"
+gdb_test "print charp" "= \\(PTR TO -> \\( character\\*1 \\)\\) $hex\( <.*>\)?"
+gdb_test "print *charp" "= 'a'"
+gdb_test "print charap" "= \\(PTR TO -> \\( character\\*3 \\)\\) $hex\( <.*>\)?"
+gdb_test "print *charap" "= 'abc'"
+gdb_test "print intp" "= \\(PTR TO -> \\( $int \\)\\) $hex\( <.*>\)?"
+gdb_test "print *intp" "= 10"
+set test_name "print intap, associated"
+gdb_test_multiple "print intap" $test_name {
+  -re "= \\(\\( 1, 1, 3(, 1){7}\\) \\( 1(, 1){9}\\) \\)\r\n$gdb_prompt $" {
+    pass $test_name
+  }
+  -re "= \\(PTR TO -> \\( $int \\(10,2\\)\\)\\) $hex\( <.*>\)?\r\n$gdb_prompt $" {
+    gdb_test "print *intap" "= \\(\\( 1, 1, 3(, 1){7}\\) \\( 1(, 1){9}\\) \\)"
+    pass $test_name
+  }
+}

Again, different outputs due to different compilers?  The latter looks
reasonable to me.


+set test_name "print intvlap, associated"
+gdb_test_multiple "print intvlap" $test_name {
+  -re "= \\(2, 2, 2, 4(, 2){6}\\)\r\n$gdb_prompt $" {
+    pass $test_name
+  }
+  -re "= \\(PTR TO -> \\( $int \\(10\\)\\)\\) $hex\( <.*>\)?\r\n$gdb_prompt $" {
+    gdb_test "print *intvlap" "= \\(2, 2, 2, 4(, 2){6}\\)"
+    pass $test_name
+  }
+}

Likewise.


diff --git a/gdb/valprint.c b/gdb/valprint.c
index 6896da2..f592278 100644
--- a/gdb/valprint.c
+++ b/gdb/valprint.c
@@ -1141,12 +1141,6 @@ value_check_printable (struct value *val, struct ui_file *stream,
        return 0;
      }
- if (type_not_associated (value_type (val))) 
-    {
-      val_print_not_associated (stream);
-      return 0;
-    }
-

Could you explain why do you remove this?
I we keep this, we shortcut any additional printing of the target type of a pointer in case it is not associated. 


    if (type_not_allocated (value_type (val)))
      {
        val_print_not_allocated (stream);


Intel Deutschland GmbH
Registered Address: Am Campeon 10-12, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de
Managing Directors: Christin Eisenschmid, Christian Lamprechter
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]