Missing extern "C"

I'm sure most of us hit the problem of that annoying linker error "unresolved external symbol "aoein0hepqo2washpeofh a@foo" (ok, I just hammered the keyboard - it's no real live symbol name!).
After triple-checking the library link list it turns out that (again) the mixing of C and C++ modules and libraries is the root of the problem.

But what to do if you have a C++ module that references an API function declared in a header file that is not prepared to be included by C++ code?

If you are not allowed to patch the file (may be its 3rd party stuff) there is a quite simple solution:

extern "C"
{
#include
}

Cheers,
Jürgen
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CommCtrl with R3 Touch broken after QFE update (Fatal error U1077)

A while ago Jochen already posted some info on Touch Gestures feature introduced in R3. So if this is coming along with Windows CE 6.0 R3 then there must be a situation to mess up things from R2 and R3.

And here it is:

Get the R3 iso image from Microsoft download center. Nearly 1.2 GB of data. But at least if that stuff in your installation gets broken you get all data to do a repair then.

Run R3 update being an incremental install to an existing Windows CE 6.0 R2 and voilá: It's working.

Now we learned one thing: Update everything to have the latest changes available! So get the QFEs!

But be aware: This might break your R3 install. If you have already done so then each blddemo will run into the following situation. Your build.log will show a fatal error:

commctrl.lib(aygutils.obj) : warning LNK4217: locally defined symbol SHCreateDefaultGradient imported in function "public: static int __cdecl AygUtils_t::SHGradientInit(struct tagSHGRADIENT *,int,unsigned short const *)" (?SHGradientInit@AygUtils_t@@SAHPAUtagSHGRADIENT@@HPBG@Z)
commctrl.lib(aygutils.obj) : warning LNK4217: locally defined symbol SHGetSystemMetrics imported in function "public: static int __cdecl AygUtils_t::SHGradientInit(struct tagSHGRADIENT *,int,unsigned short const *)" (?SHGradientInit@AygUtils_t@@SAHPAUtagSHGRADIENT@@HPBG@Z)
commctrl.lib(lvgesture.obj) : error LNK2019: unresolved external symbol "public: static void __cdecl TouchPerf::ReleaseSession(void)" (?ReleaseSession@TouchPerf@@SAXXZ) referenced in function "public: __cdecl GestureTriggeredScrollCtrl::~GestureTriggeredScrollCtrl(void)" (??1GestureTriggeredScrollCtrl@@QAA@XZ)
commctrl.lib(lvgesture.obj) : error LNK2019: unresolved external symbol "public: static void __cdecl TouchPerf::AcquireSession(void)" (?AcquireSession@TouchPerf@@SAXXZ) referenced in function "public: __cdecl GestureTriggeredScrollCtrl::GestureTriggeredScrollCtrl(void)" (??0GestureTriggeredScrollCtrl@@QAA@XZ)
C:\WinCE600\OSDesigns\???_MIPSII_FP\cesysgen\oak\target\MIPSII_FP\debug\commctrl.dll : fatal error LNK1120: 2 unresolved externals
NMAKE : fatal error U1077: 'link' : return code '0x460'
Stop.
NMAKE : fatal error U1077: 'C:\WINCE600\sdk\bin\i386\nmake.exe' : return code '0x2'
Stop.

This one can not be resolved with turning on/off catalog item selections or something like that. The current QFEs simply break your R3 install and overwrite some files but not all being related to Touch Gesture or other R3 features.

This will most likely be fixed in the upcoming QFEs again but meanwhile just re-run the R3 rollout msi (Microsoft Installer) included in the ISO image and select repair from the corresponding menu.

Until now I did not encounter any side effects after using this R3 repair.

Unfortunately it's hard to say if the R2 tree is completely merged in R3 or if some side effect might occur. If I find some time I will check that. But most likely best way is to wait for the next QFEs to get that properly fixed.

At least the repair will allow you to continue work on R3 development that way.

Merry Christmas and Best Wishes for a happy new year, and all your R2 and R3 projects...

--- Oliver
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