add_compile_options¶
Add options to the compilation of source files.
add_compile_options(<option> ...)
Adds options to the COMPILE_OPTIONS directory property.
These options are used when compiling targets from the current
directory and below.
Note
These options are not used when linking.
See the add_link_options() command for that.
Arguments¶
Arguments to add_compile_options may use generator expressions
with the syntax $<...>. See the cmake-generator-expressions(7)
manual for available expressions.  See the cmake-buildsystem(7) manual
for more on defining buildsystem properties.
Option De-duplication¶
The final set of options used for a target is constructed by accumulating options from the current target and the usage requirements of its dependencies. The set of options is de-duplicated to avoid repetition.
Added in version 3.12: While beneficial for individual options, the de-duplication step can break
up option groups.  For example, -option A -option B becomes
-option A B.  One may specify a group of options using shell-like
quoting along with a SHELL: prefix.  The SHELL: prefix is dropped,
and the rest of the option string is parsed using the
separate_arguments() UNIX_COMMAND mode. For example,
"SHELL:-option A" "SHELL:-option B" becomes -option A -option B.
Example¶
Since different compilers support different options, a typical use of this command is in a compiler-specific conditional clause:
if (MSVC)
    # warning level 4
    add_compile_options(/W4)
else()
    # additional warnings
    add_compile_options(-Wall -Wextra -Wpedantic)
endif()
To set per-language options, use the $<COMPILE_LANGUAGE>
or $<COMPILE_LANGUAGE:languages> generator expressions.
See Also¶
- This command can be used to add any options. However, for adding preprocessor definitions and include directories it is recommended to use the more specific commands - add_compile_definitions()and- include_directories().
- The command - target_compile_options()adds target-specific options.
- This command adds compile options for all languages. Use the - COMPILE_LANGUAGEgenerator expression to specify per-language compile options.
- The source file property - COMPILE_OPTIONSadds options to one source file.
- add_link_options()adds options for linking.
- CMAKE_<LANG>_FLAGSand- CMAKE_<LANG>_FLAGS_<CONFIG>add language-wide flags passed to all invocations of the compiler. This includes invocations that drive compiling and those that drive linking.
