Re: [gcc patch] Re: C++ member function template id not matching linkage name (PR debug/49408)

Jan Kratochvil
2011-06-29T20:00:47Z

On Mon, 27 Jun 2011 20:00:24 +0200, Jason Merrill wrote:
> They should be supressed whenever the function appears in an
> expression context, either as a pointer to member function (i.e. the
> operand of '&')

Done, therefore it is no longer restricted only to templates as before.

> or as the function being called in a call expression.

I implemented it in the patch below but I do not agree + understand it.

The call expression is in libiberty/testsuite/demangle-expected modified by
this patch as:

# decltype/fn call test
--format=gnu-v3
_Z4add3IidEDTclL_Z1gEfp_fp0_EET_T0_
-decltype (g({parm#1}, {parm#2})) add3<int, double>(int, double)
+decltype (g) add3<int, double>(int, double)

I agree it is sufficient to determine the return type just from the function
type as return type cannot be overloaded by the function parameters. But it
no longer matches a valid C++ source code now:

char g (int x, double y) { return 0; }
template <typename T, typename U>
decltype (g((T) 0, (U) 0)) add3 (T x, U y) { return 'z'; }
// error: ‘add3’ declared as function returning a function
// decltype (g) add3 (T x, U y) { return 'z'; }
int main () { add3<int, double> (1, 2.0); }

g++ -Wall -g -std=c++0x
g++ (GCC) 4.7.0 20110629 (experimental)

(Regression testing underway.)

Thanks,
Jan

libiberty/
2011-06-29 Jan Kratochvil <jan.kratochvil@redhat.com>

* cp-demangle.c (d_print_comp): Suppress argument list for function
references by the '&' unary operator. Keep also already processed
variant without the argument list. Suppress argument list also for
function call used in an expression.
* testsuite/demangle-expected: Remove parameters from function call
expressions of 6 testcases. Create 3 new testcases for function
references by the '&' unary operator..

--- a/libiberty/cp-demangle.c
+++ b/libiberty/cp-demangle.c
@@ -4139,7 +4169,46 @@ d_print_comp (struct d_print_info *dpi, int options,
return;

case DEMANGLE_COMPONENT_UNARY:
- if (d_left (dc)->type != DEMANGLE_COMPONENT_CAST)
+ if (d_left (dc)->type == DEMANGLE_COMPONENT_OPERATOR
+ && d_left (dc)->u.s_operator.op->len == 1
+ && d_left (dc)->u.s_operator.op->name[0] == '&'
+ && d_right (dc)->type == DEMANGLE_COMPONENT_TYPED_NAME
+ && d_left (d_right (dc))->type == DEMANGLE_COMPONENT_QUAL_NAME
+ && d_right (d_right (dc))->type == DEMANGLE_COMPONENT_FUNCTION_TYPE)
+ {
+ /* Address of a function (therefore in an expression context) must
+ have its argument list suppressed.
+
+ unary operator ... dc
+ operator & ... d_left (dc)
+ typed name ... d_right (dc)
+ qualified name ... d_left (d_right (dc))
+ <names>
+ function type ... d_right (d_right (dc))
+ argument list
+ <arguments> */
+
+ d_print_expr_op (dpi, options, d_left (dc));
+ d_print_comp (dpi, options, d_left (d_right (dc)));
+ return;
+ }
+ else if (d_left (dc)->type == DEMANGLE_COMPONENT_OPERATOR
+ && d_left (dc)->u.s_operator.op->len == 1
+ && d_left (dc)->u.s_operator.op->name[0] == '&'
+ && d_right (dc)->type == DEMANGLE_COMPONENT_QUAL_NAME)
+ {
+ /* Keep also already processed variant without the argument list.
+
+ unary operator ... dc
+ operator & ... d_left (dc)
+ qualified name ... d_right (dc)
+ <names> */
+
+ d_print_expr_op (dpi, options, d_left (dc));
+ d_print_comp (dpi, options, d_right (dc));
+ return;
+ }
+ else if (d_left (dc)->type != DEMANGLE_COMPONENT_CAST)
d_print_expr_op (dpi, options, d_left (dc));
else
{
@@ -4172,10 +4241,11 @@ d_print_comp (struct d_print_info *dpi, int options,
d_print_comp (dpi, options, d_right (d_right (dc)));
d_append_char (dpi, ']');
}
- else
+ /* Function call used in an expression should not have the argument list
+ printed. */
+ else if (strcmp (d_left (dc)->u.s_operator.op->code, "cl") != 0)
{
- if (strcmp (d_left (dc)->u.s_operator.op->code, "cl") != 0)
- d_print_expr_op (dpi, options, d_left (dc));
+ d_print_expr_op (dpi, options, d_left (dc));
d_print_subexpr (dpi, options, d_right (d_right (dc)));
}

diff --git a/libiberty/testsuite/demangle-expected b/libiberty/testsuite/demangle-expected
index bbd418c..da87282 100644
--- a/libiberty/testsuite/demangle-expected
+++ b/libiberty/testsuite/demangle-expected
@@ -3904,7 +3904,7 @@ decltype ({parm#1}+{parm#2}) add<int, double>(int, double)
# decltype/fn call test
--format=gnu-v3
_Z4add3IidEDTclL_Z1gEfp_fp0_EET_T0_
-decltype (g({parm#1}, {parm#2})) add3<int, double>(int, double)
+decltype (g) add3<int, double>(int, double)
# new (2008) built in types test
--format=gnu-v3
_Z1fDfDdDeDhDsDi
@@ -3916,15 +3916,15 @@ void f<int*, float*, double*>(int*, float*, double*)
# '.' test
--format=gnu-v3
_Z1hI1AIiEdEDTcldtfp_1gIT0_EEET_S2_
-decltype (({parm#1}.(g<double>))()) h<A<int>, double>(A<int>, double)
+decltype (({parm#1}.(g<double>))) h<A<int>, double>(A<int>, double)
# test for typed function in decltype
--format=gnu-v3
_ZN1AIiE1jIiEEDTplfp_clL_Z1xvEEET_
-decltype ({parm#1}+((x())())) A<int>::j<int>(int)
+decltype ({parm#1}+((x()))) A<int>::j<int>(int)
# test for expansion of function parameter pack
--format=gnu-v3
_Z1gIIidEEDTclL_Z1fEspplfp_Li1EEEDpT_
-decltype (f(({parm#1}+(1))...)) g<int, double>(int, double)
+decltype (f) g<int, double>(int, double)
# lambda tests
--format=gnu-v3
_ZZ1giENKUlvE_clEv
@@ -3949,10 +3949,10 @@ _Z1fIfLi4EEvDv_T0__T_
void f<float, 4>(float __vector(4))
--format=gnu-v3
_Z1fI1AEDTclonplfp_fp_EET_
-decltype ((operator+)({parm#1}, {parm#1})) f(A)
+decltype ((operator+)) f(A)
--format=gnu-v3
_Z1hI1AEDTcldtfp_miEET_
-decltype (({parm#1}.(operator-))()) h(A)
+decltype (({parm#1}.(operator-))) h(A)
--format=gnu-v3
_Z1fDn
f(decltype(nullptr))
@@ -3990,6 +3990,18 @@ outer(short (*)(int), long)
_Z6outer2IsEPFilES1_
outer2<short>(int (*)(long))
#
+--format=gnu-v3 --no-params
+_ZN1KIXadL_ZN1S1mEiEEE1fEv
+K<&S::m>::f()
+K<&S::m>::f
+--format=gnu-v3
+_ZN1KILi1EXadL_ZN1S1mEiEEE1fEv
+K<1, &S::m>::f()
+# Here the `(int)' argument list of `S::m' is already removed.
+--format=gnu-v3
+_ZN1KILi1EXadL_ZN1S1mEEEE1fEv
+K<1, &S::m>::f()
+#
# Ada (GNAT) tests.
#
# Simple test.