I did not find an elegant way to solve that MSYS bug,
but anyway qwt-6.1.3 gets built with qt-5.8 with Android API 22,
it just does not get installed.

Getting rid of libQt5PrintSupport.so dependency with
Qt Code: 
  1. CONFIG   += QT_NO_PRINTER
  2. or 
  3. DEFINES += QT_NO_PRINTER
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did not help, but that is not a show stopper.

If a stand-alone app is made out of controls example, its contols.pro could look like:
Qt Code: 
  1. QT       += core gui concurrent
  2.  
  3. greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
  4.  
  5. TARGET = controls
  6. TEMPLATE = app
  7.  
  8.  
  9. SOURCES += main.cpp \
  10.     dialbox.cpp \
  11.     dialtab.cpp \
  12.     knobbox.cpp \
  13.     knobtab.cpp \
  14.     sliderbox.cpp \
  15.     slidertab.cpp \
  16.     wheelbox.cpp \
  17.     wheeltab.cpp
  18.  
  19. HEADERS  += \
  20.     dialbox.h \
  21.     dialtab.h \
  22.     knobbox.h \
  23.     knobtab.h \
  24.     sliderbox.h \
  25.     slidertab.h \
  26.     wheelbox.h \
  27.     wheeltab.h
  28.  
  29. INCLUDEPATH += "D:\QT_LIBS\Qwt-6.1.3-svn\include"
  30. DEPENDPATH += "D:\QT_LIBS\Qwt-6.1.3-svn\include"
  31.  
  32. android {
  33.     QWT_PATH = "D:\QtProjects\build-qwt-Android_f_r_armeabi_v7a_GCC_4_9_Qt_5_8_0_715d62-Release\lib"
  34.     LIBS += -L$$QWT_PATH -lqwt
  35.     message($$QWT_PATH)
  36.     message("android")
  37. }
  38.  
  39. win32 {
  40.     LIBS += "D:\QtProjects\build-qwt-Desktop_Qt_5_8_0_MSVC2015_64bit-Release\lib\qwt.lib"
  41.     message("windows")
  42.     message($$LIBS)
  43. }
  44.  
  45. contains(ANDROID_TARGET_ARCH,armeabi-v7a) {
  46.     ANDROID_EXTRA_LIBS = \
  47.         D:/QtProjects/controls/../build-qwt-Android_f_r_armeabi_v7a_GCC_4_9_Qt_5_8_0_715d62-Release/lib/libqwt.so \
  48.         $$PWD/../../Qt/Qt-5.8.0-android/5.8/android_armv7/lib/libQt5PrintSupport.so 
  49. }
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There are some warnings about unused DT entries at the start of the app,
well, at least the app starts and works.