diff --git a/system/lib/libc/musl/arch/emscripten/bits/alltypes.h b/system/lib/libc/musl/arch/emscripten/bits/alltypes.h
index 83b834246fbf0..051245ed475d9 100644
--- a/system/lib/libc/musl/arch/emscripten/bits/alltypes.h
+++ b/system/lib/libc/musl/arch/emscripten/bits/alltypes.h
@@ -93,18 +93,6 @@ typedef struct { union { int __i[10]; volatile int __vi[10]; unsigned long __s[1
 #endif
 
 
-// TODO(kleisauke): Remove these two typedefs.
-#if defined(__NEED_pthread_mutex_t) && !defined(__DEFINED_pthread_mutex_t)
-typedef struct { union { int __i[6]; volatile int __vi[6]; volatile void * /*volatile*/__p[6]; } __u; } pthread_mutex_t;
-#define __DEFINED_pthread_mutex_t
-#endif
-
-#if defined(__NEED_mtx_t) && !defined(__DEFINED_mtx_t)
-typedef struct { union { int __i[6]; volatile int __vi[6]; volatile void * /*volatile*/__p[6]; } __u; } mtx_t;
-#define __DEFINED_mtx_t
-#endif
-
-
 // END EMSCRIPTEN-SPECIFIC DEFINITIONS
 //
 // Below here are the shared musl definitions.  The emscripten-specific definitions above will take precedence
diff --git a/system/lib/libc/musl/arch/emscripten/bits/alltypes.h.in b/system/lib/libc/musl/arch/emscripten/bits/alltypes.h.in
index 5eced059b4372..1f3168b2f8627 100644
--- a/system/lib/libc/musl/arch/emscripten/bits/alltypes.h.in
+++ b/system/lib/libc/musl/arch/emscripten/bits/alltypes.h.in
@@ -37,10 +37,6 @@ TYPEDEF struct { alignas(8) long long __ll; long double __ld; } max_align_t;
 // to pass a pointer to a string denoting the WebGL canvases to transfer.
 TYPEDEF struct { union { int __i[10]; volatile int __vi[10]; unsigned long __s[10]; } __u; const char *_a_transferredcanvases; } pthread_attr_t;
 
-// TODO(kleisauke): Remove these two typedefs.
-TYPEDEF struct { union { int __i[6]; volatile int __vi[6]; volatile void * /*volatile*/__p[6]; } __u; } pthread_mutex_t;
-TYPEDEF struct { union { int __i[6]; volatile int __vi[6]; volatile void * /*volatile*/__p[6]; } __u; } mtx_t;
-
 // END EMSCRIPTEN-SPECIFIC DEFINITIONS
 //
 // Below here are the shared musl definitions.  The emscripten-specific definitions above will take precedence
diff --git a/test/code_size/test_codesize_minimal_pthreads.json b/test/code_size/test_codesize_minimal_pthreads.json
index 9f6386080ee7e..6a09075e12795 100644
--- a/test/code_size/test_codesize_minimal_pthreads.json
+++ b/test/code_size/test_codesize_minimal_pthreads.json
@@ -1,10 +1,10 @@
 {
   "a.out.js": 7581,
   "a.out.js.gz": 3736,
-  "a.out.nodebug.wasm": 19590,
-  "a.out.nodebug.wasm.gz": 9031,
-  "total": 27171,
-  "total_gz": 12767,
+  "a.out.nodebug.wasm": 19588,
+  "a.out.nodebug.wasm.gz": 9025,
+  "total": 27169,
+  "total_gz": 12761,
   "sent": [
     "a (memory)",
     "b (emscripten_get_now)",
diff --git a/test/code_size/test_codesize_minimal_pthreads_memgrowth.json b/test/code_size/test_codesize_minimal_pthreads_memgrowth.json
index 3f8c58a76691e..651a5d967ecc8 100644
--- a/test/code_size/test_codesize_minimal_pthreads_memgrowth.json
+++ b/test/code_size/test_codesize_minimal_pthreads_memgrowth.json
@@ -1,10 +1,10 @@
 {
   "a.out.js": 8012,
   "a.out.js.gz": 3939,
-  "a.out.nodebug.wasm": 19591,
-  "a.out.nodebug.wasm.gz": 9031,
-  "total": 27603,
-  "total_gz": 12970,
+  "a.out.nodebug.wasm": 19589,
+  "a.out.nodebug.wasm.gz": 9025,
+  "total": 27601,
+  "total_gz": 12964,
   "sent": [
     "a (memory)",
     "b (emscripten_get_now)",