[TechDraw] Clean up precompile in Gui

[benj5378]

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[berndhahnebach]

for feature branch PR_7313. Pipeline 605286847 was triggered at b6a2af9. All CI branches and pipelines.

[WandererFan]

I could be wrong, but I don't think PreCompiled.h is supposed to appear in *.h files, only *.cpp. If I look at Part/App or Part/Gui, none of the *.h files have it.

[berndhahnebach]

for feature branch PR_7313. Pipeline 605629230 was triggered at 8a7b2c8. All CI branches and pipelines.

[berndhahnebach]

for feature branch PR_7313. Pipeline 605632284 was triggered at 28b8d34. All CI branches and pipelines.

[berndhahnebach]

for feature branch PR_7313. Pipeline 606007300 was triggered at 7fcafd6. All CI branches and pipelines.

[berndhahnebach]

for feature branch PR_7313. Pipeline 606013582 was triggered at bdd4b36. All CI branches and pipelines.

[benj5378]

This PR is assuming that I understood https://forum.freecadweb.org/viewtopic.php?f=10&t=70796 correctly.

I could be wrong, but I don't think PreCompiled.h is supposed to appear in *.h files, only *.cpp. If I look at Part/App or Part/Gui, none of the *.h files have it.

@wwmayer, do you know anything about this? I'd be very happy if you were able to skim the PR.

I have tested that it compiles on Ubuntu with PCH turned off @The-EG has tested, that it compiles on Windows in Visual Studio with PCH turned on Do we need any additional compiler tests?

[wwmayer]

do you know anything about this? I'd be very happy if you were able to skim the PR.

wandererfan brought up the relevant points. Adding anything about PCH into headers must be avoided. If use a type in a header you can check if a forward declaration is enough but if not then you must include the appropriate header there.

[berndhahnebach]

for feature branch PR_7313. Pipeline 612824754 was triggered at 2ffe626. All CI branches and pipelines.

[berndhahnebach]

for feature branch PR_7313. Pipeline 612901004 was triggered at e3f670d. All CI branches and pipelines.

[berndhahnebach]

for feature branch PR_7313. Pipeline 612913987 was triggered at e450300. All CI branches and pipelines.