Well in tools/options I have Enable CLang intellisense by default set to true. I have just created a brand new embedded test c++ project. It is led blink with nrf51822 and no softdevice and openocd. I inserted

static void stop_realtime_timer(void) {}

then in main function I typed stop_ and hit ctrl+space. I got stop_realtime_timerealtime_timer()

Here is console output:

[+0:04:51.568] Starting operation: Parse – HighlightBraces
[+0:04:51.569] Operation completed: Parse – HighlightBraces [1 msec]
[+0:04:52.384] Starting operation: Parse – HighlightBraces
[+0:04:52.386] Operation completed: Parse – HighlightBraces [2 msec]
[+0:04:52.830] Starting operation: Parse – HighlightBraces
[+0:04:52.832] Operation completed: Parse – HighlightBraces [2 msec]
[+0:04:53.023] Starting operation: Parse – HighlightBraces
[+0:04:53.031] Operation completed: Parse – HighlightBraces [8 msec]
[+0:04:53.216] Starting operation: Parse – QuickInfo
[+0:04:53.217] c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp has changed since last build. Doing full analysis…
[+0:04:53.220] No changed PSFs found. Doing a CodeComplete run with minimal reparsing.
[+0:04:53.273] Operation completed: Parse – QuickInfo [57 msec]
[+0:04:53.498] Starting operation: Parse – HighlightBraces
[+0:04:53.499] Operation completed: Parse – HighlightBraces [1 msec]
[+0:04:53.579] Starting operation: Parse – HighlightBraces
[+0:04:53.580] Operation completed: Parse – HighlightBraces [1 msec]
[+0:04:53.682] Starting operation: Parse – HighlightBraces
[+0:04:53.683] Operation completed: Parse – HighlightBraces [1 msec]
[+0:04:53.786] Starting operation: Parse – HighlightBraces
[+0:04:53.787] Operation completed: Parse – HighlightBraces [1 msec]
[+0:04:54.187] Starting operation: Parse – HighlightBraces
[+0:04:54.188] Operation completed: Parse – HighlightBraces [1 msec]
[+0:04:54.604] Starting operation: Parse – CompleteWord
[+0:04:54.607] Starting operation: Code Completion at LEDBlink.cpp:(24,2)
[+0:04:54.608] c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp has changed since last build. Doing full analysis…
[+0:04:54.610] No changed PSFs found. Doing a CodeComplete run with minimal reparsing.
[+0:04:54.673] Operation completed: Code Completion at LEDBlink.cpp:(24,2) [66 msec]
[+0:04:54.673] Code completion yielded 5597 suggestions (raw time: 62/48/0/3 msec)
[+0:04:54.673] Operation completed: Parse – CompleteWord [69 msec]
[+0:04:54.675] Starting operation: Merging code snippets into suggestion list
[+0:04:54.676] Operation completed: Merging code snippets into suggestion list [1 msec]
[+0:04:54.676] Starting operation: Searching completion set for “stop_”
[+0:04:54.680] Found 59 items matching stop_ out of 5613, main index = 38
[+0:04:54.680] Operation completed: Searching completion set for “stop_” [4 msec]
[+0:04:54.686] Starting operation: Parse – HighlightBraces
[+0:04:54.686] Operation completed: Parse – HighlightBraces [0 msec]
[+0:04:54.689] Starting operation: Parse – MethodTip
[+0:04:54.690] Starting operation: Function argument hint request at LEDBlink.cpp:(24,22)
[+0:04:54.690] c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp has changed since last build. Doing full analysis…
[+0:04:54.691] No changed PSFs found. Doing a CodeComplete run with minimal reparsing.
[+0:04:54.718] Operation completed: Function argument hint request at LEDBlink.cpp:(24,22) [28 msec]
[+0:04:54.718] Argument hint request yielded no results
[+0:04:54.718] Operation completed: Parse – MethodTip [29 msec]
[+0:04:59.837] Starting operation: Parse – Check
[+0:04:59.837] Starting operation: Reparsing c:\Users\osv\documents\visualgdb\EmbeddedProject1\EmbeddedProject1\LEDBlink.cpp
[+0:04:59.838] c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp has changed since last build. Doing full analysis…
[+0:04:59.841] No changed PSFs found, but c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp is outdated due to itself. Doing a quick PSF-based rebuild with 1 PSFs.
[+0:04:59.841] Starting fpsParsingFileBody on c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp
[+0:04:59.897] Starting fpsAnalyzingReferences on c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp
[+0:04:59.906] Completed fpsAnalyzingReferences on c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp
[+0:04:59.910] Completed fpsParsingFileBody on c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp
[+0:04:59.910] c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp has not changed since last build. Doing a quick recheck…
[+0:04:59.911] Saved data for c:\users\osv\documents\visualgdb\embeddedproject1\embeddedproject1\ledblink.cpp is up to date. Skipping reparsing…
[+0:04:59.912] Checked c:\Users\osv\documents\visualgdb\EmbeddedProject1\EmbeddedProject1\LEDBlink.cpp: 1 error records
[+0:04:59.913] Operation completed: Reparsing c:\Users\osv\documents\visualgdb\EmbeddedProject1\EmbeddedProject1\LEDBlink.cpp [76 msec]
[+0:04:59.913] Operation completed: Parse – Check [76 msec]

I use VS Professional 2015, version 14.0.25123.00 Update 2. It is newly reinstalled PC but my settings get synchronized by login in. I have tried /ResetUserData, /ResetSettings but with the same result…

Works fine. Thanks 😉