How to clear all defines from cmake?

Question

I have project where I need some specific preprocessor definitions. Nothing less nothing more. I tried various solutions:

set(DEFINES MY_DEFINE)
target_compile_definitions(my_target PRIVATE ${DEFINES})

and

set(DEFINES -DMY_DEFINE)
add_definitions(${DEFINES})

even

set(DEFINES MY_DEFINE)
set_property(TARGET my_target PROPERTY CACHE COMPILE_DEFINITIONS ${DEFINES})

Every time cmake still injects some other defines:

WIN32
_WINDOWS
CMAKE_INTDIR="$(CONFIG)"

My target is static library and project generator is Visual Studio 2015 if it might influence anything. How can I get cmake to set only my defines?

Defines like `WIN32` or `_WINDOWS` are needed for standard libraries. Without them, even simple `printf()` may to not work. — Tsyvarev, Nov 30 '17 at 14:33
I understand that they might be needed, but my project requires that they are not set. — ostojan, Nov 30 '17 at 18:42
Normally, platform-dependenet compiler flags come with *CMAKE_C_FLAGS*/ *CMAKE_CXX_FLAGS*. You may try to set these variable to empty value. — Tsyvarev, Nov 30 '17 at 18:55

score 3 · Accepted Answer · answered Nov 30 '17 at 21:31

3

Since those are platform specific defines in CMake, you can only remove them "globally" for your current CMakeList.txt scope (not for an idividual taret) with something like:

string(REGEX REPLACE "(-D|/D)[^ ]* " "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")

Reference

Is Cmake set variable recursive?

answered Nov 30 '17 at 21:31

Florian

39,996
9
133
149

Thanks for the link, that was my problem. I've cleared all CMAKE_CXX_FLAGS in cmake file above, so I've excepted that in all files below that file flags will be cleared. – ostojan Dec 01 '17 at 05:58
:( <-- frowny-face – iAdjunct Jul 12 '18 at 22:01

Patrick Avery · Answer 2 · 2017-11-30T16:38:17.657

0

In CMake, you can use remove_definitions for any definitions added via add_definitions. I'm not sure if that will work here, though, because cmake may not be adding them via add_definitions.

You could also potentially #undef those definitions at the very top of your C++ files. This is a little bit dirtier, but it might work.

edited Nov 30 '17 at 16:38

answered Nov 30 '17 at 16:22

Patrick Avery

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8

I thought about remove_definitions, but in that case I need to enter defines to remove directly inside my cmake file and I'm looking for cleaner (and more important - more generic) solution. – ostojan Nov 30 '17 at 18:47

How to clear all defines from cmake?

2 Answers2