Problem:    Duplicate arguments are not always detected.
Solution:   Expand to full path before comparing arguments. (Nir Lichtman,
            closes #11505, closes #9402)

Problem:    Crash when using "!!" without a previous shell command.
Solution:   Check "prevcmd" is not NULL. (closes #11487)

Problem:    col() and charcol() only work for the current window.
Solution:   Add an optional winid argument. (Yegappan Lakshmanan,
            closes #11466, closes #11461)

Problem:    Default value of 'endoffile' is wrong.
Solution:   The default must be 'noendoffile'.

Problem:    Solution for "!!sort" in closed fold is not optimal.
Solution:   Use a different range instead of the subtle difference in handling
            a range with an offset. (issue #11487)

Problem:    MS-Windows: windres fails with clang 15.0.4.
Solution:   Use llvm-windres. (John Marriott)

Problem:    Compiler warning for unused variable.
Solution:   Add #ifdef.

Problem:    "!!sort" in a closed fold sorts too many lines.
Solution:   Round to end of fold after adding the line count. (closes #11487)

Problem:    Selecting MSVC 2017 does not set $PLATFORM.
Solution:   Use $VSCMD_ARG_TGT_ARCH. (Ken Takata, closes #11485)

Problem:    MS-Windows: executable not found when running individual test.
Solution:   Also look for vimd.exe. (Christopher Plewright, closes #11525)