From: Matt Corallo <git@bluematt.me>
Date: Sat, 15 Jan 2022 22:59:11 +0000 (+0000)
Subject: Optimize more aggressively for WASM builds
X-Git-Tag: v0.0.105.0~2^2~4
X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=d8861cc16426cc3cf9809da57d55eb88871fca3d;p=ldk-c-bindings

Optimize more aggressively for WASM builds

Use `-Oz` instead of `-Os` because why not, and include LLVM
bitcode in C dependencies.

This reduces `liblightningjs_release.wasm` from 3.0MB to 2.4MB,
likely mostly from removing secp256k1 symbols that were unused.
---

diff --git a/genbindings.sh b/genbindings.sh
index 1752286..edaa01d 100755
--- a/genbindings.sh
+++ b/genbindings.sh
@@ -485,10 +485,10 @@ if [ "$2" = "false" -a "$(rustc --print target-list | grep wasm32-wasi)" != "" ]
 	echo "int main() {}" > genbindings_wasm_test_file.c
 	if clang -nostdlib -o /dev/null --target=wasm32-wasi -Wl,--no-entry genbindings_wasm_test_file.c > /dev/null 2>&1; then
 		# And if it does, build a WASM binary without capturing errors
-		export CFLAGS_wasm32_wasi="$BASE_CFLAGS -target wasm32"
+		export CFLAGS_wasm32_wasi="$BASE_CFLAGS -target wasm32 -O1"
 		RUSTFLAGS="$RUSTFLAGS --cfg=test_mod_pointers" cargo rustc $CARGO_BUILD_ARGS -v --target=wasm32-wasi
-		export CFLAGS_wasm32_wasi="$BASE_CFLAGS -target wasm32 -Os"
-		CARGO_PROFILE_RELEASE_LTO=true cargo rustc $CARGO_BUILD_ARGS -v --release --target=wasm32-wasi -- -C embed-bitcode=yes -C opt-level=s -C linker-plugin-lto -C lto
+		export CFLAGS_wasm32_wasi="$BASE_CFLAGS -fembed-bitcode -target wasm32 -Oz"
+		CARGO_PROFILE_RELEASE_LTO=true cargo rustc $CARGO_BUILD_ARGS -v --release --target=wasm32-wasi -- -C embed-bitcode=yes -C opt-level=z -C linker-plugin-lto -C lto
 	else
 		echo "Cannot build WASM lib as clang does not seem to support the wasm32-wasi target"
 	fi