Bug 13801

Summary:	toolchainfile.cmake CMAKE_BUILD_TYPE
Product:	buildroot	Reporter:	christian.morales.vega
Component:	Other	Assignee:	unassigned
Status:	RESOLVED INVALID
Severity:	normal	CC:	buildroot, s.martin49
Priority:	P5
Version:	2021.02.1
Target Milestone:	---
Hardware:	All
OS:	Linux
Host:		Target:
Build:

Description christian.morales.vega 2021-05-12 08:41:59 UTC

The toolchainfile.cmake file created by Buildroot says things like "# This toolchain file can be used both inside and outside Buildroot.". But it's not really friendly to outside Buildroot users since it hardcodes CMAKE_BUILD_TYPE.

cmake -B build -DCMAKE_BUILD_TYPE=MinSizeRel -DCMAKE_TOOLCHAIN_FILE=toolchainfile.cmake should use MinSizeRel, not Debug or Release. Maybe I want to debug my software and want to build it with Debug CMAKE_BUILD_TYPE even if the rest of Buildroot has been built with Release.


I'm not even sure how much sense it makes to make it Debug or Release based on BR2_ENABLE_DEBUG (https://git.busybox.net/buildroot/tree/package/pkg-cmake.mk?id=8036c23d5964cf924d8857cf1a8f711404458950#n269).
BR2_ENABLE_DEBUG is described as "Build packages with debugging symbols enabled", i.e. it's only effect is supposed to be to add "-g". But by using the Debug CMAKE_BUILD_TYPE God knows what a specific package will do: it may enable extra logging, use a way slower algorithm to do some task...

In any case I would argue https://git.busybox.net/buildroot/tree/package/pkg-cmake.mk?id=8036c23d5964cf924d8857cf1a8f711404458950#n94 is a better place to set a __default__ CMAKE_BUILD_TYPE. Outside Buildroot user should not be seeing it.

Comment 1 christian.morales.vega 2021-05-12 10:14:22 UTC

I was actually looking at a file doing something differently than what at least the latest Buildroot does. Since it's set as a non-forced cache variable the user's given value has priority.