Select libraries using the ICU build time version

[wscho77]

if CLR_USE_ICU_BUILD_TIME_VERSION environment variable is set, select libraries using ICU build time version.

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Issue Details

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if CLR_USE_ICU_BUILD_TIME_VERSION environment variable is set, select libraries using ICU build time version.

Author:	wscho77
Assignees:	-
Labels:	area-System.Globalization, community-contribution
Milestone:	-

[wscho77]

##79251 (comment)

[am11]

This is very niche use case. If you know that you have the exact ICU version installed as the runtime build (which is not very likely, as the official build takes place on a CentOS7 machine for compat), you can already use CLR_ICU_VERSION_OVERRIDE=<that version> without introducing another environment variable.

[wscho77]

This is very niche use case. If you know that you have the exact ICU version installed as the runtime build (which is not very likely, as the official build takes place on a CentOS7 machine for compat), you can already use CLR_ICU_VERSION_OVERRIDE=<that version> without introducing another environment variable.

One source code can be built on the multiple build environment, and the ICU version can be different for each build environment.
As you can see in this patch, build time ICU version can be obtain with "U_ICU_VERSION_MAJOR_NUM" value in the source code.
This is a different case against "CLR_ICU_VERSION_OVERRIDE".

If you set environment "CLR_USE_ICU_BUILD_TIME_VERSION=true", this patch works.

[am11]

It is the case when we know that the system has the same version installed as the runtime build, right? If so, then we should also be able to find out which version it was (e.g. in a distro's manifest file) and we can set the existing CLR_ICU_VERSION_OVERRIDE to that version for quick lookup.

[wscho77]

the case when we know that the system has the same version installed as the runtime build, right? If so, then we should also be able to find out which version it was (e.g. in a distro's manifest file) and we can set the existing CLR_ICU_VERSION_OVERRIDE to that version for quick lookup.

Mistakes can be occur if we manually specify the ICU version every time when the build environment changes.
I just want to simple and automatical way to set ICU version :)

How about follow Android case? It try to load ICU without version number. (

runtime/src/native/libs/System.Globalization.Native/pal_icushim.c

Line 186 in 2e2f9a4

static int FindICULibs(char* symbolName, char* symbolVersion)

).
Linux also provides unversioned ibrary (symlink).

[tarekgh]

@janvorli @jkotas the changes here look reasonable to me. Do you have any feedback for that?

[janvorli]

Linux also provides unversioned ibrary

This is only the build time library (from a dev package), not the runtime one. The runtime libraries are always versioned.

As for this PR, how about allowing the existing CLR_ICU_VERSION_OVERRIDE to be set also to "build" string, check for it in the FindLibUsingOverride before we start parsing the env var value for the version components and use the build time version in this case? That would not require introducing yet another env var and it seems it would logically make sense, as it is an override too.

[wscho77]

check for it in the FindLibUsingOverride before we start parsing the env var value for the version components and use the build time version in th

It would be good to use "CLR_ICU_VERSION_OVERRIDE" environment variable. I'll make a patch for it soon.

[wscho77]

@janvorli, @tarekgh I add a patch to add "build" value for CRL_ICU_VERSION_OVERRIDE".
Please review this patch.

[tarekgh]

LGTM.

[wscho77]

@tarekgh The failed checks are not related to this patch.
What should I do to pass checks?

[tarekgh]

@wscho77 thanks for your contribution here.