Re: [RFA] Fix cygwin compilation failure due to nameless LOAD_DLL_DEBUG_EVENT causes ntdll.dll to be missing

Yao Qi
2013-12-16T02:21:53Z

On 12/14/2013 06:37 AM, Pierre Muller wrote:
> introduced a failure for cygwin native build.
> The problem is that __USEWIDE is not considered in the patch.
>

For the record, the build failure is this:

cc1: warnings being treated as errors
../../git/gdb/windows-nat.c: In function ‘windows_ensure_ntdll_loaded’:
../../git/gdb/windows-nat.c:1773:11: error: passing argument 3 of ‘GetModuleFileNameEx’ from incompatible pointer type
../../git/gdb/windows-nat.c:1773:11: note: expected ‘LPWSTR’ but argument is of type ‘char *’
Makefile:998: recipe for target `windows-nat.o' failed

> The patch below fixes this compilation error
> and should allow cygwin to work as mingw.
>
> Pierre Muller
>
>
> ChangeLog entry:
>
> 2013-12-13 Pierre Muller <muller@sourceware.org>
>
> Fix compilation error for cygwin native build.
> * windows-nat.c (windows_ensure_ntdll_loaded): Add
> code using wchar_t type and conversion to char string
> if __USEWIDE is defined.

Probably, we can write

(windows_ensure_ntdll_loaded) [__USEWIDE]: Call
wcstombs.

>
>
> diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
> index f0545fc..dda9d8e 100644
> --- a/gdb/windows-nat.c
> +++ b/gdb/windows-nat.c
> @@ -1764,17 +1764,27 @@ windows_ensure_ntdll_loaded (void)
> for (i = 0; i < (int) (cb_needed / sizeof (HMODULE)); i++)
> {
> MODULEINFO mi;
> +#ifdef __USEWIDE
> + wchar_t dll_name[__PMAX];
> + char name[__PMAX];
> +#else
> char dll_name[__PMAX];
> -
> + char *name;
> +#endif
> if (GetModuleInformation (current_process_handle, hmodules[i],
> &mi, sizeof (mi)) == 0)
> continue;
> if (GetModuleFileNameEx (current_process_handle, hmodules[i],
> dll_name, sizeof (dll_name)) == 0)
> continue;
> - if (FILENAME_CMP (lbasename (dll_name), "ntdll.dll") == 0)
> +#ifdef __USEWIDE
> + wcstombs (name, dll_name, __PMAX);
> +#else
> + name = dll_name;
> +#endif
> + if (FILENAME_CMP (lbasename (name), "ntdll.dll") == 0)
> {
> - solib_end->next = windows_make_so (dll_name, mi.lpBaseOfDll);
> + solib_end->next = windows_make_so (name, mi.lpBaseOfDll);
> solib_end = solib_end->next;
> return;
> }

GetModuleFileNameEx is also used in get_module_name, so probably we can
copy its pattern here too

#ifdef __CYGWIN__
len = GetModuleFileNameEx (current_process_handle, DllHandle,
pathbuf, __PMAX);
if (cygwin_conv_path (CCP_WIN_W_TO_POSIX, pathbuf, dll_name_ret,
__PMAX) < 0)
...
#else
len = GetModuleFileNameEx (current_process_handle,
DllHandle, dll_name_ret, __PMAX);
#endif

and code is more consistent on using GetModuleFileNameEx.
--
Yao (é½å°§)