diff --git a/compiler/builtins/bitcode/src/str.zig b/compiler/builtins/bitcode/src/str.zig
index febbef5be4..74047b4995 100644
--- a/compiler/builtins/bitcode/src/str.zig
+++ b/compiler/builtins/bitcode/src/str.zig
@@ -310,11 +310,9 @@ const c = @cImport({
 
 // Str.fromFloat
 // When we actually use this in Roc, libc will be linked so we have access to std.heap.c_allocator
-pub fn strFromFloatC(int: i64) callconv(.C) RocStr {
-    // const foobar = @bitCast(f32, @intCast(i32, float));
-    // const result = std.fmt.allocPrint(std.heap.c_allocator, "{}", .{@as(f32, foobar)}) catch unreachable;
-    const float = @bitCast(f64, int);
-
+pub fn strFromFloatC(float: f64) callconv(.C) RocStr {
+    // NOTE the compiled zig for float formatting seems to use LLVM11-specific features
+    // hopefully we can use zig instead of snprintf in the future when we upgrade
     var buf: [100]u8 = undefined;
 
     const result = c.snprintf(&buf, 100, "%f", float);
diff --git a/compiler/gen/src/llvm/build_str.rs b/compiler/gen/src/llvm/build_str.rs
index f190f83a08..ba15b095ec 100644
--- a/compiler/gen/src/llvm/build_str.rs
+++ b/compiler/gen/src/llvm/build_str.rs
@@ -281,11 +281,8 @@ pub fn str_from_float<'a, 'ctx, 'env>(
     int_symbol: Symbol,
 ) -> BasicValueEnum<'ctx> {
     let float = load_symbol(scope, &int_symbol);
-    let int = env
-        .builder
-        .build_bitcast(float, env.context.i64_type(), "to_bits");
 
-    let zig_result = call_bitcode_fn(env, &[int], &bitcode::STR_FROM_FLOAT).into_struct_value();
+    let zig_result = call_bitcode_fn(env, &[float], &bitcode::STR_FROM_FLOAT).into_struct_value();
 
     zig_str_to_struct(env, zig_result).into()
 }