[Gold856]

This is completely removed in C++26. Suppressing warnings is not enough, and is a hard error on clang-cl with -std=c++latest.

[Gold856]

I noticed #689 cites a commit where the warning was suppressed instead of changing the code, but even then before that PR was made, a different ImGui commit was made where the code was changed, so this PR actually keeps things more in-line with how ImGui does things.

[brenocq]

Thanks @Gold856, fixing the code instead of silencing the warning is the right call, and it matches what ImGui does.

I merged master into the branch and added a commit that applies the same cast in two more places. The first is the demo, at the two ImPlotItemFlags_NoLegend | ImPlotLineFlags_Shaded sites. The demo's own Clang pragmas were hiding them, so I removed those pragmas. The second is the ImPlotSpec usage comments in implot.h, so users who copy that pattern don't hit the C++26 error.

To test it, I built implot.cpp, implot_items.cpp and implot_demo.cpp with g++ 16, g++ 13 and clang++ 23 from -std=c++11 to -std=c++2c, using -Wall -Wextra -pedantic -Werror -Wdeprecated-enum-enum-conversion against ImGui 1.92.4 and 1.93.0. Everything builds clean. With the pragmas removed, clang++ -std=c++2c fails on master and passes with this PR.

I couldn't reproduce the clang-cl error because I don't have a Windows SDK here. A Linux-target clang-cl /std:c++latest builds master, since the pragmas apply there too. Either way, the change makes sense.