# How do I disable "Perfoming Test CXX\_HAS..."

**URL:** https://discourse.cmake.org/t/how-do-i-disable-perfoming-test-cxx-has/7439
**Category:** Usage
**Created:** [February 9, 2023, 11:02pm UTC](https://discourse.cmake.org/t/how-do-i-disable-perfoming-test-cxx-has/7439 "2023-02-09T23:02:26Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Russell\_Schultz](https://discourse.cmake.org/user_avatar/discourse.cmake.org/russell_schultz/32/282_2.png) [@Russell\_Schultz](https://discourse.cmake.org/u/Russell_Schultz)
#### Post date: [February 9, 2023, 11:02pm UTC](https://discourse.cmake.org/t/how-do-i-disable-perfoming-test-cxx-has/7439/1 "2023-02-09T23:02:26Z")

</div>

We’re in a controlled build environment (our tools are fixed and do not change) and these tests really slow down the configure phase. (especially when we’re very far away from our FlexLM server since each one fires off a build/link). For example, when I’m at the office directly next to our server, a configure phase can last a minute or two. When I’m at home via vpn, I’ve seen it last up to 20 minutes. (may also have been driven by floating licenses being consumed elsewhere)

Is there a way we can disable these tests? They don’t provide us any service since our tools would not change out from underneath us.

FWIW, I’ve tried -DCMAKE\_CXX\_COMPILER\_WORKS=1 but that doesn’t seem to stop these functionality tests.

---

<div class="post-metadata">

### Author: ![scivision](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@scivision](https://discourse.cmake.org/u/scivision)
#### Post date: [February 12, 2023, 1:06am UTC](https://discourse.cmake.org/t/how-do-i-disable-perfoming-test-cxx-has/7439/2 "2023-02-12T01:06:57Z")

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Are these tests in CMakeLists.txt or those internal to CMake itself?

```cmake
cmake_minimum_required(VERSION 3.19)
project(b LANGUAGES CXX)

```

That makes at least 3 calls to the C++ compiler via `execute_process()`.

In any case, do you see anything taking particularly long in

```plaintext
cmake -B build --profiling-output=perf.json --profiling-format=google-trace

```

To view the profile data, type in Chrome or Edge address bar `about:tracing` and Load perf.json.