mingw build failure with Windows header

[Ralf Habacker]

An error was reported by openSUSE Build Service at ​https://bugzilla.opensuse.org/show_bug.cgi?id=1205190 that xapian core could not be built with mingw gcc12.

The reason for this problem is the extensive use of "using namespace std" in the sources, which makes the definition of 'byte'

enum class byte : unsigned char;

maps from the std namespace into the global namespace, which then conflicts with definitions from Windows headers:

/usr/i686-w64-mingw32/sys-root/mingw/include/rpcndr.h:397:170: error: reference to 'byte' is ambiguous

and within the source code:

 ./common/internaltypes.h:32:17: note: 'typedef uint8_t byte'
    32 | typedef uint8_t byte;

A corresponding patch based on version 1.4.21 that fixes the problem can be found at ​https://build.opensuse.org/package/view_file/windows:mingw:win32/mingw32-xapian-core/xapian-core-1.4.21-std-fixes.patch?expand=1.

[Olly Betts]

Thanks for the patch, but this problem was addressed years ago (2018) by f527b61a65f259ce68b11ef9d89a959f5cf62a12 which was in xapian-core 1.4.8 - since then the typedef uint8_t byte; line isn't present in common/internaltypes.h (or anywhere else).

It looks to me like your bug reporter must have been using xapian-core 1.4.7 or earlier to get this error.

The use of using namespace std; has been cleaned up on git master. I'm reluctant to apply such changes to 1.4.x as they touch a lot of code and it's hard to be certain they won't introduce bugs.

[Olly Betts]

Ah yes, ​https://build.opensuse.org/request/show/1034701 seems to show the problem was found with 1.4.5.

Please try dropping the patch from your build to check that this has indeed already been addressed.

[Olly Betts]

No response from submitter, but I'm confident we've addressed this already so closing.

If you can reproduce the problem with unpatched 1.4.21 (or later once there are newer versions) please comment with details and we can reopen.