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tools/cross-compiler/src/main.rs

@@ -35,6 +35,21 @@ fn main() -> anyhow::Result<()> {
         let mut rust_flags = String::new();
         rust_flags.push_str("-D warnings");
 
+        // This is part of a workaround to make `getrandom` build when compiling
+        // for WASM. See comment in `fj-viewer`'s `Cargo.toml` for more
+        // information.
+        //
+        // Setting the flag like this might not be appropriate, as it might
+        // require a similar workaround from users of `fj-viewer`. However, as
+        // of this writing (2025-05-08), `fj-viewer doesn't support the WASM
+        // target in any meaningful way. It is only compiled to that target
+        // during the CI build, to prevent regressions that would inhibit adding
+        // support harder from slipping in.
+        //
+        // So given this context, the following workaround is probably fine.
+        // Once real support for `fj-viewer` in WASM environments is added, we
+        // probably have to come up with a different solution. (And then, we'll
+        // be in a better position to actually test these different solutions.)
         if target.triple == "wasm32-unknown-unknown" {
             rust_flags.push_str(" --cfg getrandom_backend=\"wasm_js\"");
         }