CMAKE_COLOR_DIAGNOSTICS

Enable color diagnostics throughout.

This variable uses three states: ON, OFF and not defined.

When not defined:

• Makefile Generators initialize the CMAKE_COLOR_MAKEFILE variable to ON. It controls color buildsystem messages.
• GNU/Clang compilers are not invoked with any color diagnostics flag.

When ON:

• Makefile Generators produce color buildsystem messages by default. CMAKE_COLOR_MAKEFILE is not initialized, but may be explicitly set to OFF to disable color buildsystem messages.
• GNU/Clang compilers are invoked with a flag enabling color diagnostics (-fcolor-diagnostics).

When OFF:

• Makefile Generators do not produce color buildsystem messages by default. CMAKE_COLOR_MAKEFILE is not initialized, but may be explicitly set to ON to enable color buildsystem messages.
• GNU/Clang compilers are invoked with a flag disabling color diagnostics (-fno-color-diagnostics).

If the CMAKE_COLOR_DIAGNOSTICS environment variable is set, its value is used. Otherwise, CMAKE_COLOR_DIAGNOSTICS is not defined by default.