[PATCH 1/4] testcase - pointer to member function

Yao Qi
2012-11-22T07:32:41Z

Hi,
The new test cases expose some problem in GDB on handling member
pointers, and there are two fails shown below on current GDB trunk.

print (diamond.*diamond_pfunc_ptr) (20)^M
Non-pointer-to-member value used in pointer-to-member construct^M
FAIL: gdb.cp/member-ptr.exp: print (diamond.*diamond_pfunc_ptr)(20)

ptype (a.*pmf)(3)^M
type = int (A * const, int)^M
FAIL: gdb.cp/member-ptr.exp: ptype (a.*pmf)(3)

The following patches will fix them.

gdb/testsuite:

2012-11-22 Daniel Jacobowitz <dan@codesourcery.com>

* gdb.cp/member-ptr.cc (class Diamond): Add func_ptr.
(func): New function.
(main): Initialize diamond.func_ptr and add diamond_pfunc_ptr.
* gdb.cp/member-ptr.exp: Add new tests for ptype and for
pointers to members with pointer-to-function type.
---
gdb/testsuite/gdb.cp/member-ptr.cc | 17 +++++++++++++++++
gdb/testsuite/gdb.cp/member-ptr.exp | 28 ++++++++++++++++++++++++++++
2 files changed, 45 insertions(+), 0 deletions(-)

diff --git a/gdb/testsuite/gdb.cp/member-ptr.cc b/gdb/testsuite/gdb.cp/member-ptr.cc
index 17f022c..6cb87ef 100644
--- a/gdb/testsuite/gdb.cp/member-ptr.cc
+++ b/gdb/testsuite/gdb.cp/member-ptr.cc
@@ -137,6 +137,7 @@ class Diamond : public Padding, public Left, public Right
{
public:
virtual int vget_base ();
+ int (*func_ptr) (int);
};

int Diamond::vget_base ()
@@ -144,6 +145,12 @@ int Diamond::vget_base ()
return this->Left::x + 2000;
}

+int
+func (int x)
+{
+ return 19 + x;
+}
+
int main ()
{
A a;
@@ -161,6 +168,7 @@ int main ()
int (Diamond::*right_vpmf) ();
int (Base::*base_vpmf) ();
int Diamond::*diamond_pmi;
+ int (* Diamond::*diamond_pfunc_ptr) (int);

PMI null_pmi;
PMF null_pmf;
@@ -178,6 +186,7 @@ int main ()

diamond.Left::x = 77;
diamond.Right::x = 88;
+ diamond.func_ptr = func;

/* Some valid pointer to members from a base class. */
left_pmf = (int (Diamond::*) ()) (int (Left::*) ()) (&Base::get_x);
@@ -192,11 +201,19 @@ int main ()
/* A pointer to data member from a base class. */
diamond_pmi = (int Diamond::*) (int Left::*) &Base::x;

+ /* A pointer to data member, where the member is itself a pointer to
+ a function. */
+ diamond_pfunc_ptr = (int (* Diamond::*) (int)) &Diamond::func_ptr;
+
null_pmi = NULL;
null_pmf = NULL;

pmi = NULL; /* Breakpoint 1 here. */

+ // Invalid (uses diamond_pfunc_ptr as a function):
+ // diamond.*diamond_pfunc_ptr (20);
+ (diamond.*diamond_pfunc_ptr) (20);
+
k = (a.*pmf)(3);

pmi = &A::jj;
diff --git a/gdb/testsuite/gdb.cp/member-ptr.exp b/gdb/testsuite/gdb.cp/member-ptr.exp
index f569ca9..ae2b8b4 100644
--- a/gdb/testsuite/gdb.cp/member-ptr.exp
+++ b/gdb/testsuite/gdb.cp/member-ptr.exp
@@ -376,6 +376,33 @@ gdb_test_multiple "print ((int) pmi) == ((char *) &a.j - (char *) & a)" $name {
}
}

+# Check pointers to data members, which are themselves pointers to
+# functions. These behave like data members, not like pointers to
+# member functions.
+
+gdb_test "ptype diamond_pfunc_ptr" \
+ "type = int \\(\\*Diamond::\\*\\)\\(int\\)"
+
+gdb_test "ptype diamond.*diamond_pfunc_ptr" \
+ "type = int \\(\\*\\)\\(int\\)"
+
+# This one is invalid; () binds more tightly than .*, so it tries to
+# call the member pointer as a normal pointer-to-function.
+
+gdb_test "print diamond.*diamond_pfunc_ptr (20)" \
+ "Invalid data type for function to be called."
+
+# With parentheses, it is valid.
+
+gdb_test "print (diamond.*diamond_pfunc_ptr) (20)" \
+ "$vhn = 39"
+
+# Make sure that we do not interpret this as either a member pointer
+# call or a member function call.
+
+gdb_test "print diamond.func_ptr (20)" \
+ "$vhn = 39"
+
# ==========================
# pointer to member function
# ==========================
@@ -595,6 +622,7 @@ gdb_test_multiple "print (a.*pmf)(3)" $name {
}

gdb_test "ptype a.*pmf" "type = int \\(A \\*( const)?, int\\)"
+gdb_test "ptype (a.*pmf)(3)" "type = int"

# Print out a pointer to data member which requires looking into
# a base class.
--
1.7.7.6