Since support for WebAssembly 1.0 was just introduced in the nightly builds of
Firefox and Chromium, I gave it a try and things look good, at least with
firefox-nightly. The following nim.cfg
@if emscripten:
cc = clang
clang.exe = "emcc"
clang.linkerexe = "emcc"
clang.options.linker = ""
cpu = "i386"
passC = "-s WASM=1 -s 'BINARYEN_METHOD=\"native-wasm\"' -Iemscripten"
passL = "-s WASM=1 -Lemscripten -s TOTAL_MEMORY=335544320"
# use ALLOW_MEMORY_GROWTH=1 instead of TOTAL_MEMORY if performance isn't
top priority
@end
lets one compile Nim to native wasm by setting -d:emscripten on the command
line.
Trying something crazy first, I took [Araqs version of JohnS's GC test
from](https://forum.nim-lang.org/t/2646#16384) and it compiled successfully
with
nim c -d:useRealtimeGC -d:release -d:emscripten --out=index.html GCBench.nim
The result actually seems to work in the broswer, the HTML page has an output
text area showing this:
Worst push time: 1000000 nano seconds
[GC] total memory: 275017728
[GC] occupied memory: 274141184
[GC] stack scans: 4092
[GC] stack cells: 1
[GC] cycle collections: 0
[GC] max threshold: 0
[GC] zct capacity: 1024
[GC] max cycle table size: 0
[GC] max pause time [ms]: 1
[GC] max stack size: 64
The GC claims it is actually doing something and I am inclined to believe it
