[Ace] Support -fPIC compiler flag on Linux

[pierrebizz]

Add fpic feature to enable the -fPIC flag in order to be able to link ACE/TAO in a dynamic library

• Which triplets are supported/not supported? Have you updated the CI baseline?

  ,

• Does your PR follow the maintainer guide?

  Yes

• If you have added/updated a port: Have you run ./vcpkg x-add-version --all and committed the result?

[Hoikas]

My understanding is that vcpkg prefers to always pass -fPIC, so this should not be a feature, rather just a bugfix.

[cenit]

My understanding is that vcpkg prefers to always pass -fPIC, so this should not be a feature, rather just a bugfix.

yes, i think this is the rule here. Please remove the feature and apply the flag always

[pierrebizz]

Very well; is there a risk that it will break the builds of people already using this config without the fPIC flag ?

[Neumann-A]

This is a case for z_vcpkg_get_cmake_vars and not manually adding flags.

[pierrebizz]

Can someone more intelligent than me explain what exactly failed in the x64_windows_static build ?

[cenit]

Error: vcpkg has crashed; no additional details are available.
The source line is D:\a\_work\1\s\src\vcpkg\binarycaching.cpp(554)

not related to your PR.
vcpkg ci is somehow broken, HTTP remotes are pointing to non-existing address (err 403)

[pierrebizz]

Do I have to do something to retrigger ?

[cenit]

you can merge with master if your branch is not already fully up to date, or you can just wait for a maintainer with the power to launch an /azp run command

[jwillemsen]

At the moment you build ACE/TAO as shared library we do add -fPIC already to the compiler flags, no need to do that manually. As far as I know vcpkg does a static build, at that moment -fPIC is not used

[jwillemsen]

Ok, I read in the discussion that vcpkg always wants to use -fPIC

[Cheney-W]

@pierrebizz Could you please solve the conflict?

[github-actions]

This is a new experimental fast check for PR issues. Please let us know if this bot is helpful!

After committing all other changes, the version database must be updated

git add -u && git commit
git checkout d2b22891a13123accac084b5feabfd0914f4e243 -- versions
./vcpkg x-add-version --all

Diff

diff --git a/versions/a-/ace.json b/versions/a-/ace.json
index d30da3e..b9dd64e 100644
--- a/versions/a-/ace.json
+++ b/versions/a-/ace.json
@@ -1,7 +1,7 @@
 {
   "versions": [
     {
-      "git-tree": "016c4bb6add08e6e2b82254adb14e0d49a298e48",
+      "git-tree": "d20fc0a9eac1744ff9fb5c5427eade58234e35c9",
       "version": "7.0.6",
       "port-version": 3
     },

[ras0219-msft]

@Neumann-A's point is correct, the best long term solution is to use vcpkg_cmake_get_vars() from the vcpkg-cmake helper and not to hardcode flags.

However, without someone signed up to do that work, I don't want to block this reasonable incremental improvement. @pierrebizz I'd encourage you to consider submitting a PR that uses the above function to get the full set of CMake settings, which would greatly improve compatibility in more ways than just -fPIC.

Thanks again!