libiconv detection failure when compiling with full language support about video

[titobrasolin]

I closed pull request #11
#13 seems to work

[mirko]

Do you have the resources to investigate any further why -fpermissive seems to fix the issue?
Usually it rather mitigates, instead of actually fixes the issue.

[titobrasolin]

@mirko I agree with you, the GNU libiconv detection succeeds because -fpermissive downgrades some errors to warnings, but I would prefer a more targeted solution.

Without -fpermissive the detection fails here: https://github.com/qt/qtbase/blob/v5.9.1/config.tests/unix/gnu-libiconv/gnu-libiconv.cpp#L52

I'm going to investigate, but usually I have some time only during the weekend.

[titobrasolin]

Possible solution: patch gnu-libiconv.cpp to pass a non-const inbuffer?

[titobrasolin]

Interesting discussion and possible patch here:
https://bugreports.qt.io/browse/QTBUG-63529

[mirko]

Was probably related to this still existing bug: https://bugreports.qt.io/projects/QTBUG/issues/QTBUG-84708?filter=reportedbyme