In hindsight my emscripten-ifdef (70d416a8f63f) is nonsense.
As fpcrtl_glShaderSource() would not be defined and lead to compiling issues.
So either it's 3 ifdefs (in pas2cRedo, pas2cSystem and misc.c),
in order to toggle between fpcrtl_ and the native function,
or alternatively have no ifdef for it at all.
I'm going with none at all,
which means emscripten will compile with the original (const) function prototype,
being wrapped by the fpcrtl_ function, same as non-emscripten builds.
@echo off
::edit these variables if necessary
set BUILD_TYPE="Debug"
::set if vcpkg is not on path
set VCPKG_PATH=%VCPKG_ROOT%
::set if CMake is not on path
set CMAKE_PATH=
::set if FPC is not on path
set PASCAL_PATH=
:setup
set CURRDIR="%CD%"
cd %CURRDIR%\..\
set PATH=%PASCAL_PATH%;%VCPKG_PATH%;%CMAKE_PATH%;%PATH%
echo Running cmake...
set ERRORLEVEL=
cmake . -DCMAKE_TOOLCHAIN_FILE="%VCPKG_PATH%\scripts\buildsystems\vcpkg.cmake" -G"NMake Makefiles" -DNOPNG=1 -DNOSERVER=1 -DNOVIDEOREC=1 -DCMAKE_BUILD_TYPE="%BUILD_TYPE%" -DSDL2_BUILDING_LIBRARY=1
if %ERRORLEVEL% NEQ 0 goto exitpoint
echo Configuration completed successfully
echo Building...
set ERRORLEVEL=
nmake
if %ERRORLEVEL% NEQ 0 goto exitpoint
echo Build completed successfully
:exitpoint
cd %CURRDIR%
pause