# How to find all the include folders for a target for a static analyzer?

**URL:** https://discourse.cmake.org/t/how-to-find-all-the-include-folders-for-a-target-for-a-static-analyzer/3233
**Category:** Code
**Created:** [April 28, 2021, 10:40pm UTC](https://discourse.cmake.org/t/how-to-find-all-the-include-folders-for-a-target-for-a-static-analyzer/3233 "2021-04-28T22:40:53Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![JRR](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/j/ecccb3/32.png) [@JRR](https://discourse.cmake.org/u/JRR)
#### Post date: [April 28, 2021, 10:40pm UTC](https://discourse.cmake.org/t/how-to-find-all-the-include-folders-for-a-target-for-a-static-analyzer/3233/1 "2021-04-28T22:40:53Z")

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We want to add a the cppcheck static analyzer to a product and it has input arguments such as:

```auto
cppcheck <files> \
        --xml \
        --force \
        --output-file=results\cppcheck \
        --error-exitcode=1 \
        --enable=performance \
        -I include/ \
        -I internal/ \
        -I ...

```

For a given target it’s pretty easy to get a list of all the source files.

However, I’m not able to easily get all of the `-I` folders.

I thought it might be the contents of the `INCLUDE_DIRECTORIES` property, but that doesn’t seem to have the include folders that come from packages we’ve added using `find_package()` and `target_link_libraries(...package)`

I checked the `INCLUDE_DIRECTORIES` property using message()

I added logic to the end of my cmakefile that used `get_property()` to get the targets `INCLUDE_DIRECTORIES` value and then print it using `message()`

Any suggestions on how to proceed?

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<div class="post-metadata">

### Author: ![JRR](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/j/ecccb3/32.png) [@JRR](https://discourse.cmake.org/u/JRR)
#### Post date: [April 28, 2021, 10:58pm UTC](https://discourse.cmake.org/t/how-to-find-all-the-include-folders-for-a-target-for-a-static-analyzer/3233/2 "2021-04-28T22:58:23Z")

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Hmmmm… so reading about generator expressions I found a section that uses INCLUDE\_DIRECTORIES as the example.

I made a custom command

```auto
add_custom_command(TARGET ${TARGET_LIB}
    PRE_BUILD
    COMMAND ECHO "===================================================="
    COMMAND echo "foo -I $<JOIN:$<TARGET_PROPERTY:${TARGET_LIB},INCLUDE_DIRECTORIES>, -I >"
    COMMAND ECHO "===================================================="
)

```

And it is indeed showing me all of the include directories.

However, if I do

```auto
    get_property(propVal TARGET ${TARGET_LIB} PROPERTY INCLUDE_DIRECTORIES)
    if (propVal)
        message("${target}-INCLUDE_DIRECTORIES: ${propVal}")
    endif()

```

I only get one include folder. Why would I get different values?

---

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### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [April 29, 2021, 10:21am UTC](https://discourse.cmake.org/t/how-to-find-all-the-include-folders-for-a-target-for-a-static-analyzer/3233/3 "2021-04-29T10:21:07Z")

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The `INCLUDE_DIRECTORIES` property at configure time is just the set added explicitly via `target_include_directories` (and maybe `include_directories`, though that may just be stored on the directory and not gathered until generate time). At generate time, the set of linked libraries is finally known and usage requirements from the targets that are linked may be looked up and expanded (with, e.g., platform detection genexes expanded too). It’s not something you can query at configure time, so your `add_custom_command` is one way to do it properly.

You might be able to use [`CMAKE_EXPORT_COMPILE_COMMANDS`](https://cmake.org/cmake/help/latest/variable/CMAKE_EXPORT_COMPILE_COMMANDS.html) to generate `compile_commands.json` and have cppcheck use that instead.

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<div class="post-metadata">

### Author: ![JRR](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/j/ecccb3/32.png) [@JRR](https://discourse.cmake.org/u/JRR)
#### Post date: [April 29, 2021, 7:04pm UTC](https://discourse.cmake.org/t/how-to-find-all-the-include-folders-for-a-target-for-a-static-analyzer/3233/4 "2021-04-29T19:04:46Z")

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Thank you Ben!

I didn’t realize there was this sort of difference for properties during configuration time and generation time.

I will need to re-think some of the debugging methods I’ve used in the past.

We were able to make a custom command `cppcheck` that uses the INCLUDE\_DIRECTORIES property and it’s working great!

We’re still experimenting with the command and syntax but we have:

```auto
add_custom_target(
        cppcheck
        COMMAND /usr/bin/cppcheck
        "${CMAKE_CURRENT_LIST_DIR}/source/*.cpp"
        "--xml"
        "--force"
        "--output-file=${CMAKE_CURRENT_LIST_DIR}/results/"
        "--error-exitcode=1"
        "--enable=performance"    
        "-I $<JOIN:$<TARGET_PROPERTY:${TARGET},INCLUDE_DIRECTORIES>, -I >"
) 

```

Which we can invoke with

```auto
cmake --build . -v --target cppcheck

```

And it’s happily working!