Fix fail in mi-var-child.exp and mi-var-display.exp

Hi,
I see the following fails on arm-none-eabi target,

-var-list-children --simple-values struct_declarations  ^M
^done,numchild="11",children=[...,child={name="struct_declarations.func_ptr_struct",exp="func_ptr_struct",numchild="0",value="0x0 <_ftext>",type="struct _struct_decl (*)(int, char *, long)",thread-id="1"},child={name="struct_declarations.func_ptr_ptr",exp="func_ptr_ptr",numchild="0",value="0x0 <_ftext>",type="struct _struct_decl *(*)(int, char *, long)",thread-id="1"},...
(gdb) ^M
FAIL: gdb.mi/mi-var-child.exp: listing of children, simple types: names, type and values, complex types: names and types

-var-set-format weird.func_ptr_ptr natural^M
^done,format="natural",value="0x0 <_ftext>"^M
(gdb) ^M
FAIL: gdb.mi/mi-var-display.exp: set format variable weird.func_ptr_ptr in natural

In the test, "0x0" is expected, but "0x0 <_ftext>" is in the output.
Function pointers point to address zero, and tests assume there is no
symbol on address zero.  However, on my arm-none-eabi target, there is
a code symbol _ftext on address zero, and test fails.  Note that "set
print symbol off" doesn't take effect for function pointer.

int (*f) (void);
f = main;

(gdb) p f
$1 = (int (*)(void)) 0x8048400 <main>
(gdb) set print symbol off
(gdb) p f
$2 = (int (*)(void)) 0x8048400 <main>

In order to erase the difference, we can assign some function address
explicitly to function pointer, so the test behaves in a unique way.
In this patch, we assign nothing1 and nothing2 to function pointers
func_ptr_struct and func_ptr_ptr respectively, and update test as the
source file is changed.

gdb/testsuite:

2014-10-14  Yao Qi  <yao@codesourcery.com>

	* gdb.mi/mi-var-child.c (nothing1): New function.
	(nothing2): New function.
	(do_children_tests): Set function pointers by nothing1 and
	nothing2.
	* gdb.mi/mi-var-child.exp: Step over new added statements.
	Update test to match the new output.
	* gdb.mi/var-cmd.c (nothing1): New function.
	(nothing2): New function.
	(do_children_tests): Set function pointers by  nothing1 and
	nothing2.
	* gdb.mi/mi-var-display.exp: Update test to match output.
	Step to the line specified by $line_dct_nothing.
	Increase the number of lines to step.

5 files changed, 53 insertions, 10 deletions

diff --git a/gdb/testsuite/gdb.mi/mi-var-child.c b/gdb/testsuite/gdb.mi/mi-var-child.c
index bde668e..689fe55 100644
--- a/gdb/testsuite/gdb.mi/mi-var-child.c
+++ b/gdb/testsuite/gdb.mi/mi-var-child.c
@@ -160,6 +160,20 @@ nothing ()
 {
 }
 
+struct _struct_decl
+nothing1 (int a, char *b, long c)
+{
+  struct _struct_decl foo;
+
+  return foo;
+}
+
+struct _struct_decl *
+nothing2 (int a, char *b, long c)
+{
+  return (struct _struct_decl *) 0;
+}
+
 void
 subroutine1 (int i, long *l)
 {
@@ -231,6 +245,8 @@ do_children_tests (void)
   struct_declarations.long_array[9] = 1234;
 
   weird->func_ptr = nothing;
+  weird->func_ptr_struct = nothing1;
+  weird->func_ptr_ptr = nothing2;
   struct_declarations.long_array[10] = 3456;
   struct_declarations.long_array[11] = 5678;
 
diff --git a/gdb/testsuite/gdb.mi/mi-var-child.exp b/gdb/testsuite/gdb.mi/mi-var-child.exp
index 1f547ba..88be094 100644
--- a/gdb/testsuite/gdb.mi/mi-var-child.exp
+++ b/gdb/testsuite/gdb.mi/mi-var-child.exp
@@ -766,9 +766,21 @@ mi_step_to do_children_tests {} ".*${srcfile}" \
 mi_varobj_update * {struct_declarations.func_ptr} \
     "update all vars struct_declarations.func_ptr changed"
 
-# Step over "struct_declarations.long_array[10] = 3456";
+# Step over "weird->func_ptr_struct = nothing1"
 mi_step_to do_children_tests {} ".*${srcfile}" \
     [expr $line_dct_nothing + 2] "step \$line_dct_nothing + 2"
+mi_varobj_update * {struct_declarations.func_ptr_struct} \
+    "update all vars struct_declarations.func_ptr_struct changed"
+
+# Step over "weird->func_ptr_ptr = nothing2"
+mi_step_to do_children_tests {} ".*${srcfile}" \
+    [expr $line_dct_nothing + 3] "step \$line_dct_nothing + 3"
+mi_varobj_update * {struct_declarations.func_ptr_ptr} \
+    "update all vars struct_declarations.func_ptr_ptr changed"
+
+# Step over "struct_declarations.long_array[10] = 3456";
+mi_step_to do_children_tests {} ".*${srcfile}" \
+    [expr $line_dct_nothing + 4] "step \$line_dct_nothing + 4"
 
 mi_gdb_test "-var-update --no-values *" \
 	"\\^done,changelist=\\\[\{name=\"struct_declarations.long_array.10\",in_scope=\"true\",type_changed=\"false\",has_more=\"0\"\}\\\]" \
@@ -807,10 +819,10 @@ mi_list_varobj_children {struct_declarations --simple-values} \
          [list struct_declarations.int_ptr_ptr int_ptr_ptr 1 "int \\*\\*" "$hex"] \
          {struct_declarations.long_array long_array 12 "long \\[12\\]"} \
          [list struct_declarations.func_ptr func_ptr 0 "void \\(\\*\\)\\((void)?\\)" "(@$hex: |)$hex <nothing>"] \
-         {struct_declarations.func_ptr_struct func_ptr_struct 0 \
-              "struct _struct_decl \\(\\*\\)(\\(int, char \\*, long\\))?" 0x0} \
-         {struct_declarations.func_ptr_ptr func_ptr_ptr 0 \
-              "struct _struct_decl \\*\\(\\*\\)\\((int, char \\*, long)?\\)" 0x0} \
+         [list struct_declarations.func_ptr_struct func_ptr_struct 0 \
+              "struct _struct_decl \\(\\*\\)(\\(int, char \\*, long\\))?" "$hex <nothing1>"] \
+         [list struct_declarations.func_ptr_ptr func_ptr_ptr 0 \
+              "struct _struct_decl \\*\\(\\*\\)\\((int, char \\*, long)?\\)" "$hex <nothing2>"] \
          {struct_declarations.u1 u1 4 "union \\{\\.\\.\\.\\}"} \
          {struct_declarations.s2 s2 4 "struct \\{\\.\\.\\.\\}"} \
 ] "listing of children, simple types: names, type and values, complex types: names and types"
diff --git a/gdb/testsuite/gdb.mi/mi-var-display.exp b/gdb/testsuite/gdb.mi/mi-var-display.exp
index 02c2212..9f0ade5 100644
--- a/gdb/testsuite/gdb.mi/mi-var-display.exp
+++ b/gdb/testsuite/gdb.mi/mi-var-display.exp
@@ -290,7 +290,7 @@ mi_gdb_test "-var-set-format weird.func_ptr_struct hexadecimal" \
 	"set format variable weird.func_ptr_struct"
 
 mi_gdb_test "-var-set-format weird.func_ptr_ptr natural" \
-	"\\^done,format=\"natural\",value=\"0x0\"" \
+	"\\^done,format=\"natural\",value=\"$hex <nothing2>\"" \
 	"set format variable weird.func_ptr_ptr in natural"
 
 mi_gdb_test "-var-set-format weird.u1 natural" \
diff --git a/gdb/testsuite/gdb.mi/mi2-var-child.exp b/gdb/testsuite/gdb.mi/mi2-var-child.exp
index 6ae3e0c..fffc1f1 100644
--- a/gdb/testsuite/gdb.mi/mi2-var-child.exp
+++ b/gdb/testsuite/gdb.mi/mi2-var-child.exp
@@ -759,9 +759,8 @@ mi_varobj_update * {struct_declarations.long_array.3
 
 
 # Step over "weird->func_ptr = nothing;"
-set line_dct_a0_0 [gdb_get_line_number "a0\[0\] = '0';"]
-mi_step_to do_children_tests {} {.*var-cmd.c} \
-    $line_dct_a0_0 "step \$line_dct_a0_0"
+mi_step_to do_children_tests {} ".*${srcfile}" \
+    [expr $line_dct_nothing + 1] "step \$line_dct_nothing + 1"
 
 # Test: c_variable-5.9
 # Desc: check that func_ptr changed
@@ -782,7 +781,7 @@ mi_gdb_test "-var-delete weird->int_ptr_ptr" \
 #   psnp = &snp0;
 
 set line_dct_snp0 [gdb_get_line_number "psnp = &snp0;"]
-mi_execute_to "exec-step 43" "end-stepping-range" do_children_tests {} {.*var-cmd.c} \
+mi_execute_to "exec-step 45" "end-stepping-range" do_children_tests {} {.*var-cmd.c} \
     [expr $line_dct_snp0 + 1] {} "step \$line_dct_snp0 + 1"
 
 # Test: c_variable-5.10
diff --git a/gdb/testsuite/gdb.mi/var-cmd.c b/gdb/testsuite/gdb.mi/var-cmd.c
index 4bb2746..bbfbc34 100644
--- a/gdb/testsuite/gdb.mi/var-cmd.c
+++ b/gdb/testsuite/gdb.mi/var-cmd.c
@@ -182,6 +182,20 @@ nothing ()
 {
 }
 
+struct _struct_decl
+nothing1 (int a, char *b, long c)
+{
+  struct _struct_decl foo;
+
+  return foo;
+}
+
+struct _struct_decl *
+nothing2 (int a, char *b, long c)
+{
+  return (struct _struct_decl *) 0;
+}
+
 void
 subroutine1 (int i, long *l)
 {
@@ -253,6 +267,8 @@ do_children_tests (void)
   struct_declarations.long_array[9] = 1234;
 
   weird->func_ptr = nothing;
+  weird->func_ptr_struct = nothing1;
+  weird->func_ptr_ptr = nothing2;
 
   /* Struct/pointer/array tests */
   a0[0] = '0';