[PATCH][gdb/testsuite] Fix gdb.cp/break-f-std-string.cc with older gcc

[PATCH][gdb/testsuite] Fix gdb.cp/break-f-std-string.cc with older gcc

[Tom de Vries]

Hi,

When running test-case gdb.cp/break-f-std-string.exp on openSUSE Leap 15.3
with system gcc 7.5.0, I run into:
...
(gdb) whatis /r std::string^M
No symbol "string" in namespace "std".^M
(gdb) FAIL: gdb.cp/break-f-std-string.exp: _GLIBCXX_USE_CXX11_ABI=1: \
  whatis /r std::string
...
The same for gcc 8.2.1, but it passes with gcc 9.3.1.

At source level (as we can observe in the .ii file with -save-temps) we have
indeed:
...
namespace std {
  namespace __cxx11 {
    typedef basic_string<char> string;
  }
}
...
while with gcc 9.3.1, we have instead:
...
namespace std {
  namespace __cxx11 {
    ...
  }
  typedef basic_string<char> string;
}
...
due to gcc commit 33b43b0d8cd ("Define std::string and related typedefs
outside __cxx11 namespace").

Fix this by adding the missing typedef for gcc version 5 (the first version to
have the dual abi) to 8 (the last version missing aforementioned gcc commit).

Tested on x86_64-linux, with:
- system gcc 7.5.0
- gcc 4.8.5, 8.2.1, 9.3.1, 10.3.0, 11.2.1
- clang 8.0.1, 12.0.1

Any comments?

Thanks,
- Tom

[gdb/testsuite] Fix gdb.cp/break-f-std-string.cc with older gcc

---
 gdb/testsuite/gdb.cp/break-f-std-string.cc | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/gdb/testsuite/gdb.cp/break-f-std-string.cc b/gdb/testsuite/gdb.cp/break-f-std-string.cc
index 454ab4c42ea..cbbfeebac60 100644
--- a/gdb/testsuite/gdb.cp/break-f-std-string.cc
+++ b/gdb/testsuite/gdb.cp/break-f-std-string.cc
@@ -17,6 +17,20 @@
 
 #include <string>
 
+#if _GLIBCXX_USE_CXX11_ABI == 1
+#if defined (__GNUC__) && (__GNUC__ >= 5) && (__GNUC__ <= 8)
+
+// Work around missing std::string typedef before gcc commit
+// "Define std::string and related typedefs outside __cxx11 namespace".
+
+namespace std {
+using namespace __cxx11;
+typedef __cxx11::string string;
+}
+
+#endif
+#endif
+
 void
 f (std::string s)
 {

Re: [PATCH][gdb/testsuite] Fix gdb.cp/break-f-std-string.cc with older gcc

[Pedro Alves]

On 2022-05-12 12:45, Tom de Vries wrote:

> [gdb/testsuite] Fix gdb.cp/break-f-std-string.cc with older gcc
> 
> ---
>  gdb/testsuite/gdb.cp/break-f-std-string.cc | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/gdb/testsuite/gdb.cp/break-f-std-string.cc b/gdb/testsuite/gdb.cp/break-f-std-string.cc
> index 454ab4c42ea..cbbfeebac60 100644
> --- a/gdb/testsuite/gdb.cp/break-f-std-string.cc
> +++ b/gdb/testsuite/gdb.cp/break-f-std-string.cc
> @@ -17,6 +17,20 @@
>  
>  #include <string>
>  
> +#if _GLIBCXX_USE_CXX11_ABI == 1
> +#if defined (__GNUC__) && (__GNUC__ >= 5) && (__GNUC__ <= 8)
> +
> +// Work around missing std::string typedef before gcc commit
> +// "Define std::string and related typedefs outside __cxx11 namespace".

Since we try to follow the GDB conventions in the tests too, this should
use /**/ comments.

> +
> +namespace std {
> +using namespace __cxx11;

Why is this "using namespace __cxx11;" needed?  I guess something about the
"related typedefs" mentioned in the comment?  The test passes for me without
that, on GCC 6.5 (the only affected compiler I have handy atm), like:

namespace std {
typedef __cxx11::string string;
}

Otherwise LGTM.

Pedro Alves

> +typedef __cxx11::string string;
> +}
> +
> +#endif
> +#endif
> +
>  void
>  f (std::string s)
>  {
> 

Re: [PATCH][gdb/testsuite] Fix gdb.cp/break-f-std-string.cc with older gcc

[Tom de Vries]

On 5/12/22 14:47, Pedro Alves wrote:
> On 2022-05-12 12:45, Tom de Vries wrote:
> 
>> [gdb/testsuite] Fix gdb.cp/break-f-std-string.cc with older gcc
>>
>> ---
>>   gdb/testsuite/gdb.cp/break-f-std-string.cc | 14 ++++++++++++++
>>   1 file changed, 14 insertions(+)
>>
>> diff --git a/gdb/testsuite/gdb.cp/break-f-std-string.cc b/gdb/testsuite/gdb.cp/break-f-std-string.cc
>> index 454ab4c42ea..cbbfeebac60 100644
>> --- a/gdb/testsuite/gdb.cp/break-f-std-string.cc
>> +++ b/gdb/testsuite/gdb.cp/break-f-std-string.cc
>> @@ -17,6 +17,20 @@
>>   
>>   #include <string>
>>   
>> +#if _GLIBCXX_USE_CXX11_ABI == 1
>> +#if defined (__GNUC__) && (__GNUC__ >= 5) && (__GNUC__ <= 8)
>> +
>> +// Work around missing std::string typedef before gcc commit
>> +// "Define std::string and related typedefs outside __cxx11 namespace".
> 
> Since we try to follow the GDB conventions in the tests too, this should
> use /**/ comments.
> 

Ack, fixed.

>> +
>> +namespace std {
>> +using namespace __cxx11;
> 
> Why is this "using namespace __cxx11;" needed?  I guess something about the
> "related typedefs" mentioned in the comment?  The test passes for me without
> that, on GCC 6.5 (the only affected compiler I have handy atm), like:
> 
> namespace std {
> typedef __cxx11::string string;
> }
> 

Works for me as well, so removed.

> Otherwise LGTM.
> 

Thanks for the review, committed.

Thanks,
- Tom

> Pedro Alves
> 
>> +typedef __cxx11::string string;
>> +}
>> +
>> +#endif
>> +#endif
>> +
>>   void
>>   f (std::string s)
>>   {
>>
>