* [patch/rfc] Test struct0
@ 2004-02-04 0:06 Andrew Cagney
2004-02-04 0:46 ` Daniel Jacobowitz
2004-02-10 21:07 ` Andrew Cagney
0 siblings, 2 replies; 6+ messages in thread
From: Andrew Cagney @ 2004-02-04 0:06 UTC (permalink / raw)
To: gdb-patches
[-- Attachment #1: Type: text/plain, Size: 547 bytes --]
Hello,
This adds a test for:
struct foo0 { };
to the structs.exp testcase (I'm assuming that this is legal ISO-C), it
passes on PPC with stabs with:
> (gdb) PASS: gdb.base/structs.exp: ptype foo1; structs-tc
> p/c fun0()
> $1 = {<No data fields>}
Tt was intended for completness, however with a dwarf2 compiler:
amd64$ gcc --version
gcc (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-24)
> (gdb) PASS: gdb.base/structs.exp: ptype foo1; structs-tc
> p/c fun0()
> $1 = <incomplete type>
I guess I should file a bug report and kfail it?
Andrew
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[-- Type: text/plain, Size: 2696 bytes --]
2004-02-03 Andrew Cagney <cagney@redhat.com>
* gdb.base/structs.c (struct struct0): Define.
(foo0, L0): New variables.
(fun0, Fun0): New functions.
(main): Call fun0 and Fun0.
* gdb.base/structs.exp: Test zero sized structure.
(foo): Add output from an empty struct.
Index: testsuite/gdb.base/structs.c
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.base/structs.c,v
retrieving revision 1.5
diff -u -r1.5 structs.c
--- testsuite/gdb.base/structs.c 20 Nov 2003 17:11:55 -0000 1.5
+++ testsuite/gdb.base/structs.c 3 Feb 2004 23:34:47 -0000
@@ -86,6 +86,7 @@
typedef tQ tR;
#endif
+struct struct0 {};
struct struct1 {tA a;};
struct struct2 {tA a; tB b;};
struct struct3 {tA a; tB b; tC c; };
@@ -105,6 +106,7 @@
struct struct17 {tA a; tB b; tC c; tD d; tE e; tF f; tG g; tH h; tI i; tJ j; tK k; tL l; tM m; tN n; tO o; tP p; tQ q; };
struct struct18 {tA a; tB b; tC c; tD d; tE e; tF f; tG g; tH h; tI i; tJ j; tK k; tL l; tM m; tN n; tO o; tP p; tQ q; tR r; };
+struct struct0 foo0 = {}, L0;
struct struct1 foo1 = {'1'}, L1;
struct struct2 foo2 = {'a','2'}, L2;
struct struct3 foo3 = {'1','b','3'}, L3;
@@ -124,6 +126,10 @@
struct struct17 foo17 = {'1','b','3','d','5','f','7','h','9','j','B','l','D','n','F','p','H'}, L17;
struct struct18 foo18 = {'a','2','c','4','e','6','g','8','i','A','k','C','m','E','o','G','q','I'}, L18;
+struct struct0 fun0()
+{
+ return foo0;
+}
struct struct1 fun1()
{
return foo1;
@@ -198,6 +204,15 @@
}
#ifdef PROTOTYPES
+void Fun0(struct struct0 foo0)
+#else
+void Fun0(foo0)
+ struct struct0 foo0;
+#endif
+{
+ L0 = foo0;
+}
+#ifdef PROTOTYPES
void Fun1(struct struct1 foo1)
#else
void Fun1(foo1)
@@ -408,6 +423,7 @@
#endif
int i;
+ Fun0(foo0);
Fun1(foo1);
Fun2(foo2);
Fun3(foo3);
@@ -435,6 +451,7 @@
while (1)
{
zed ();
+ L0 = fun0();
L1 = fun1();
L2 = fun2();
L3 = fun3();
Index: testsuite/gdb.base/structs.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.base/structs.exp,v
retrieving revision 1.17
diff -u -r1.17 structs.exp
--- testsuite/gdb.base/structs.exp 4 Jan 2004 15:04:41 -0000 1.17
+++ testsuite/gdb.base/structs.exp 3 Feb 2004 23:34:47 -0000
@@ -118,7 +118,7 @@
proc foo { n } {
return [lindex {
- "{}"
+ "{<No data fields>}"
"{a = 49 '1'}"
"{a = 97 'a', b = 50 '2'}"
"{a = 49 '1', b = 98 'b', c = 51 '3'}"
@@ -481,6 +481,7 @@
# original "structs" test was doing.
start_structs_test { tc }
+test_struct_calls 0
test_struct_calls 1
test_struct_calls 2
test_struct_calls 3
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [patch/rfc] Test struct0
2004-02-04 0:06 [patch/rfc] Test struct0 Andrew Cagney
@ 2004-02-04 0:46 ` Daniel Jacobowitz
2004-02-04 1:34 ` Joel Brobecker
2004-02-04 15:52 ` Andrew Cagney
2004-02-10 21:07 ` Andrew Cagney
1 sibling, 2 replies; 6+ messages in thread
From: Daniel Jacobowitz @ 2004-02-04 0:46 UTC (permalink / raw)
To: gdb-patches
On Tue, Feb 03, 2004 at 07:06:47PM -0500, Andrew Cagney wrote:
> Hello,
>
> This adds a test for:
>
> struct foo0 { };
>
> to the structs.exp testcase (I'm assuming that this is legal ISO-C), it
Nope.
struct-or-union-specifier:
struct-or-union identifier-opt { struct-declaration-list }
struct-or-union identifier
struct-or-union:
struct
union
struct-declaration-list:
struct-declaration
struct-declaration-list struct-declaration
struct-declaration:
specifier-qualifier-list struct-declarator-list ;
So there must be a minimum of one declarator and trailing semicolon
inside the braces. GCC will warn about this if you ask it to - it's
probably -ansi, or -std=c89 -ansi -pedantic.
While it's not legal C, I believe that it is legal C++.
> passes on PPC with stabs with:
>
> >(gdb) PASS: gdb.base/structs.exp: ptype foo1; structs-tc
> >p/c fun0()
> >$1 = {<No data fields>}
>
> Tt was intended for completness, however with a dwarf2 compiler:
>
> amd64$ gcc --version
> gcc (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-24)
>
> >(gdb) PASS: gdb.base/structs.exp: ptype foo1; structs-tc
> >p/c fun0()
> >$1 = <incomplete type>
>
> I guess I should file a bug report and kfail it?
If you want to add the test anyway and run it where it compiles, then
yeah. I assume this runs afoul of the handling for declarations/opaque
types. It would be nice to support it even if it's a GNU extension.
--
Daniel Jacobowitz
MontaVista Software Debian GNU/Linux Developer
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [patch/rfc] Test struct0
2004-02-04 0:46 ` Daniel Jacobowitz
@ 2004-02-04 1:34 ` Joel Brobecker
2004-02-04 15:52 ` Andrew Cagney
1 sibling, 0 replies; 6+ messages in thread
From: Joel Brobecker @ 2004-02-04 1:34 UTC (permalink / raw)
To: gdb-patches
> While it's not legal C, I believe that it is legal C++.
And the equivalent is legal in Ada too.
(We have two equivalent forms:
type Empty is record
end record;
or a shorter version:
type Empty is null record;
)
I was about to have a look at this for us, actually. So if we
open a PR, it can be assigned to me.
--
Joel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [patch/rfc] Test struct0
2004-02-04 0:46 ` Daniel Jacobowitz
2004-02-04 1:34 ` Joel Brobecker
@ 2004-02-04 15:52 ` Andrew Cagney
2004-02-04 15:59 ` Daniel Jacobowitz
1 sibling, 1 reply; 6+ messages in thread
From: Andrew Cagney @ 2004-02-04 15:52 UTC (permalink / raw)
To: Daniel Jacobowitz; +Cc: gdb-patches
> On Tue, Feb 03, 2004 at 07:06:47PM -0500, Andrew Cagney wrote:
>
>> Hello,
>>
>> This adds a test for:
>>
>> struct foo0 { };
>>
>> to the structs.exp testcase (I'm assuming that this is legal ISO-C), it
>
>
> Nope.
I guess I misunderstood Jim's comments.
http://sources.redhat.com/ml/gdb-patches/2004-01/msg00717.html
> struct-or-union-specifier:
> struct-or-union identifier-opt { struct-declaration-list }
> struct-or-union identifier
>
> struct-or-union:
> struct
> union
>
> struct-declaration-list:
> struct-declaration
> struct-declaration-list struct-declaration
>
> struct-declaration:
> specifier-qualifier-list struct-declarator-list ;
>
> So there must be a minimum of one declarator and trailing semicolon
> inside the braces. GCC will warn about this if you ask it to - it's
> probably -ansi, or -std=c89 -ansi -pedantic.
> While it's not legal C, I believe that it is legal C++.
But are you sure? :-) If it's legal C++ then it, along with some other
wierd-o edge cases should probably be added to a gdb.cp/struct0 test
(someone with less rusty C++ than me can probably come up with a list).
Trying to include it in structs.exp would just be too messy.
Andrew
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [patch/rfc] Test struct0
2004-02-04 15:52 ` Andrew Cagney
@ 2004-02-04 15:59 ` Daniel Jacobowitz
0 siblings, 0 replies; 6+ messages in thread
From: Daniel Jacobowitz @ 2004-02-04 15:59 UTC (permalink / raw)
To: gdb-patches
On Wed, Feb 04, 2004 at 10:52:09AM -0500, Andrew Cagney wrote:
> >On Tue, Feb 03, 2004 at 07:06:47PM -0500, Andrew Cagney wrote:
> >
> >>Hello,
> >>
> >>This adds a test for:
> >>
> >> struct foo0 { };
> >>
> >>to the structs.exp testcase (I'm assuming that this is legal ISO-C), it
> >
> >
> >Nope.
>
> I guess I misunderstood Jim's comments.
> http://sources.redhat.com/ml/gdb-patches/2004-01/msg00717.html
Hmm, the comment isn't very clear. Yes, this is a GNU extension
(though not many people seem to know it).
> > struct-or-union-specifier:
> > struct-or-union identifier-opt { struct-declaration-list }
> > struct-or-union identifier
> >
> > struct-or-union:
> > struct
> > union
> >
> > struct-declaration-list:
> > struct-declaration
> > struct-declaration-list struct-declaration
> >
> > struct-declaration:
> > specifier-qualifier-list struct-declarator-list ;
> >
> >So there must be a minimum of one declarator and trailing semicolon
> >inside the braces. GCC will warn about this if you ask it to - it's
> >probably -ansi, or -std=c89 -ansi -pedantic.
>
> >While it's not legal C, I believe that it is legal C++.
>
> But are you sure? :-) If it's legal C++ then it, along with some other
> wierd-o edge cases should probably be added to a gdb.cp/struct0 test
> (someone with less rusty C++ than me can probably come up with a list).
>
> Trying to include it in structs.exp would just be too messy.
Yeah. Of course, there's the interesting property that zero-element
structures have non-zero size in C++. That's because they're a
first-class part of the language. Consider:
struct foo { };
struct foo bar[10];
int baz = sizeof (bar);
In GNU C, baz is initialized to zero. In GNU C++ (i386-linux, but I
think all targets since the v3 ABI covers this), baz is initialized to
ten. One byte per zero-sized struct is wasted in order to preserve
monotonically increasing array element addresses. Then, in some cases
(all dealing with base classes), the one byte is optimized away again.
--
Daniel Jacobowitz
MontaVista Software Debian GNU/Linux Developer
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [patch/rfc] Test struct0
2004-02-04 0:06 [patch/rfc] Test struct0 Andrew Cagney
2004-02-04 0:46 ` Daniel Jacobowitz
@ 2004-02-10 21:07 ` Andrew Cagney
1 sibling, 0 replies; 6+ messages in thread
From: Andrew Cagney @ 2004-02-10 21:07 UTC (permalink / raw)
To: gdb-patches
> Hello,
>
> This adds a test for:
>
> struct foo0 { };
>
> to the structs.exp testcase (I'm assuming that this is legal ISO-C), it passes on PPC with stabs with:
>
> (gdb) PASS: gdb.base/structs.exp: ptype foo1; structs-tc
> p/c fun0()
> $1 = {<No data fields>}
>
> Tt was intended for completness, however with a dwarf2 compiler:
>
> amd64$ gcc --version
> gcc (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-24)
>
> (gdb) PASS: gdb.base/structs.exp: ptype foo1; structs-tc
> p/c fun0()
> $1 = <incomplete type>
>
> I guess I should file a bug report and kfail it?
I'm dropping this patch - it isn't valid C. If someone want's to come
up with a C++ equivalent, feel free.
Andrew
^ permalink raw reply [flat|nested] 6+ messages in thread
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2004-02-04 0:06 [patch/rfc] Test struct0 Andrew Cagney
2004-02-04 0:46 ` Daniel Jacobowitz
2004-02-04 1:34 ` Joel Brobecker
2004-02-04 15:52 ` Andrew Cagney
2004-02-04 15:59 ` Daniel Jacobowitz
2004-02-10 21:07 ` Andrew Cagney
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