diff --git a/src/apis/emscripten/env.rs b/src/apis/emscripten/env.rs
index 4db47ed99..9ae2d9de5 100644
--- a/src/apis/emscripten/env.rs
+++ b/src/apis/emscripten/env.rs
@@ -1,6 +1,6 @@
 use super::super::host;
 /// NOTE: These syscalls only support wasm_32 for now because they take u32 offset
-use libc::{c_int, c_void, close, exit, open, read, size_t, ssize_t};
+use libc::{c_int};
 use std::ffi::CStr;
 use std::os::raw::c_char;
 
diff --git a/src/apis/emscripten/memory.rs b/src/apis/emscripten/memory.rs
index e9a39f96d..e568108b3 100644
--- a/src/apis/emscripten/memory.rs
+++ b/src/apis/emscripten/memory.rs
@@ -25,7 +25,7 @@ pub extern "C" fn get_total_memory(instance: &mut Instance) -> u32 {
 }
 
 /// emscripten: enlargeMemory
-pub extern "C" fn enlarge_memory(instance: &mut Instance) {
+pub extern "C" fn enlarge_memory(_instance: &mut Instance) {
     debug!("emscripten::enlarge_memory");
     // instance.memories[0].grow(100);
 }
diff --git a/src/apis/emscripten/mod.rs b/src/apis/emscripten/mod.rs
index 121ff9504..54c8a0a24 100644
--- a/src/apis/emscripten/mod.rs
+++ b/src/apis/emscripten/mod.rs
@@ -10,7 +10,6 @@ mod utils;
 
 // SYSCALLS
 pub use self::utils::is_emscripten_module;
-use super::host;
 
 pub fn generate_emscripten_env<'a, 'b>() -> ImportObject<&'a str, &'b str> {
     let mut import_object = ImportObject::new();
diff --git a/src/apis/emscripten/syscalls.rs b/src/apis/emscripten/syscalls.rs
index 59c27b794..62c40bf6a 100644
--- a/src/apis/emscripten/syscalls.rs
+++ b/src/apis/emscripten/syscalls.rs
@@ -1,10 +1,6 @@
 /// NOTE: These syscalls only support wasm_32 for now because they take u32 offset
 /// Syscall list: https://www.cs.utexas.edu/~bismith/test/syscalls/syscalls32.html
-use libc::{c_int, c_void, close, exit, open, read, size_t, ssize_t, write};
-use std::{mem, ptr};
-
-use std::ffi::CStr;
-use std::os::raw::c_char;
+use libc::{c_int, c_void, ssize_t, write};
 
 use crate::webassembly::Instance;
 
@@ -12,22 +8,22 @@ use crate::webassembly::Instance;
 macro_rules! vararg {
     ($name:ident, $type:ident, $instance:ident, $varargs:ident) => (
         let ($name, $varargs) = unsafe {
+            use std::ptr;
             let ptr = $instance.memory_offset_addr(0, $varargs as usize);
             let ret = ptr::read(ptr as *const $type);
             (ret, $varargs + 4)
-        }
+        };
     )
 }
 
 /// sys_read
-pub extern "C" fn ___syscall3(which: c_int, varargs: c_int, instance: &mut Instance) -> ssize_t {
+pub extern "C" fn ___syscall3(_which: c_int, _varargs: c_int, _instance: &mut Instance) -> ssize_t {
     debug!("emscripten::___syscall3");
     0
 }
 
 /// sys_write
-#[no_mangle]
-pub extern "C" fn ___syscall4(which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
+pub extern "C" fn ___syscall4(_which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
     debug!("emscripten::___syscall4");
     vararg!(fd, i32, instance, varargs);
     vararg!(buf_ptr, u32, instance, varargs);
@@ -38,7 +34,7 @@ pub extern "C" fn ___syscall4(which: c_int, varargs: c_int, instance: &mut Insta
 }
 
 /// sys_open
-pub extern "C" fn ___syscall5(which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
+pub extern "C" fn ___syscall5(_which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
     debug!("emscripten::___syscall5");
     vararg!(pathname, u32, instance, varargs);
     vararg!(flags, u32, instance, varargs);
@@ -48,8 +44,7 @@ pub extern "C" fn ___syscall5(which: c_int, varargs: c_int, instance: &mut Insta
 }
 
 // sys_ioctl
-#[no_mangle]
-pub extern "C" fn ___syscall54(which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
+pub extern "C" fn ___syscall54(_which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
     debug!("emscripten::___syscall54");
     vararg!(stream, u32, instance, varargs);
     vararg!(op, u32, instance, varargs);
@@ -58,8 +53,7 @@ pub extern "C" fn ___syscall54(which: c_int, varargs: c_int, instance: &mut Inst
 }
 
 // sys_newuname
-#[no_mangle]
-pub extern "C" fn ___syscall122(which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
+pub extern "C" fn ___syscall122(_which: c_int, varargs: c_int, instance: &mut Instance) -> c_int {
     debug!("emscripten::___syscall122");
     vararg!(buf, u32, instance, varargs);
     debug!("buf: {}", buf);
diff --git a/src/apis/emscripten/utils.rs b/src/apis/emscripten/utils.rs
index e28ab26e2..bbc659a0c 100644
--- a/src/apis/emscripten/utils.rs
+++ b/src/apis/emscripten/utils.rs
@@ -2,7 +2,7 @@ use crate::webassembly::module::Module;
 
 /// We check if a provided module is an Emscripten generated one
 pub fn is_emscripten_module(module: &Module) -> bool {
-    for (module, field) in &module.info.imported_funcs {
+    for (module, _field) in &module.info.imported_funcs {
         if module == "env" {
             return true;
         }
diff --git a/src/apis/gcc/.gitignore b/src/apis/gcc/.gitignore
deleted file mode 100644
index e69de29bb..000000000
diff --git a/src/apis/host/posix/env.rs b/src/apis/host/posix/env.rs
index 00830a796..b0fff8174 100644
--- a/src/apis/host/posix/env.rs
+++ b/src/apis/host/posix/env.rs
@@ -1,12 +1,7 @@
-/// NOTE: These syscalls only support wasm_32 for now because they take u32 offset
-use libc::{c_int, c_void, close, exit, open, read, size_t, ssize_t};
-use std::ffi::CStr;
-use std::os::raw::c_char;
-
 use crate::webassembly::Instance;
 use std::env;
 
-pub extern "C" fn get_env(name: &str, instance: &mut Instance) -> Result<String, env::VarError> {
+pub extern "C" fn get_env(name: &str, _instance: &mut Instance) -> Result<String, env::VarError> {
     debug!("host::get_env({:?})", name);
     env::var(name)
 }
diff --git a/src/apis/llvm/.gitignore b/src/apis/llvm/.gitignore
deleted file mode 100644
index e69de29bb..000000000
diff --git a/src/webassembly/mod.rs b/src/webassembly/mod.rs
index c985f1ff0..143eb1c66 100644
--- a/src/webassembly/mod.rs
+++ b/src/webassembly/mod.rs
@@ -7,7 +7,6 @@ pub mod module;
 pub mod relocation;
 pub mod utils;
 
-use cranelift_codegen::isa::TargetIsa;
 use cranelift_codegen::{isa, settings};
 use std::panic;
 use std::str::FromStr;
diff --git a/src/webassembly/module.rs b/src/webassembly/module.rs
index f3fc0ea55..6d217c82a 100644
--- a/src/webassembly/module.rs
+++ b/src/webassembly/module.rs
@@ -43,10 +43,10 @@ pub fn native_pointer_size() -> i32 {
 }
 
 /// Convert a TlsData offset into a `Offset32` for a global decl.
-fn offset32(offset: usize) -> ir::immediates::Offset32 {
-    assert!(offset <= i32::max_value() as usize);
-    (offset as i32).into()
-}
+// fn offset32(offset: usize) -> ir::immediates::Offset32 {
+//     assert!(offset <= i32::max_value() as usize);
+//     (offset as i32).into()
+// }
 
 /// Convert a usize offset into a `Imm64` for an iadd_imm.
 fn imm64(offset: usize) -> ir::immediates::Imm64 {