Set compile flags in Emscripten toolchain?

How can I pass an Emscripten compile flag to the toolchain? Specifically, I need to change use:

or one of the settings that adjust the total allowable memory. As a note, the default memory limit for a web build is way too low.

I’m foggy (at best) on how the whole Emscripten toolchain thing works, so any help is most appreciated!

Use the build option to control this compiler flag. See … ld_Options for more detail. Scroll to those options prefixed by “EMSCRIPTEN_”.