Failed to compile source code with BUILD_SHARED_LIBS on

[zhang-qiang-github]

1. Firstly, I can successfully build bullet3 from source code with BUILD_SHARED_LIBS off.
2. When I set BUILD_SHARED_LIBS on, it report bug:

1>OpenGL_DebugFont.obj : error LNK2001:  cannot resolve external symbol glad_glColorPointer
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glBlendFunc
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glPushClientAttrib
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glPushMatrix
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glVertexPointer
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glGetIntegerv
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glBindTexture
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glGetFloatv
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glGetTexEnviv
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glPopClientAttrib
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glColor4ubv
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glScissor
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glGetBooleanv
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glViewport
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glOrtho
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glEnable
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glPopAttrib
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glGenTextures
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glPopMatrix
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glDisable
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glMatrixMode
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glAlphaFunc
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glTexParameteri
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glPushAttrib
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glTexEnvi
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glLineWidth
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glDrawArrays
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glEnableClientState
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glLoadIdentity
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glTexCoordPointer
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glFlush
1>OpenGL_DebugFont.obj : error LNK2001: cannot resolve external symbol glad_glTexImage2D
1>D:\bullet3_2\build\lib\Debug\gwen_Debug.dll : fatal error LNK1120: 32 unresolved external symbols
1>The operation to generate the project "gwen.vcxproj" has completed - Failed.

What should I do?