diff --git a/minicoro.h b/minicoro.h
index bb691a7..900ef6d 100644
--- a/minicoro.h
+++ b/minicoro.h
@@ -1114,13 +1114,23 @@ int _mco_switch(_mco_ctxbuf* from, _mco_ctxbuf* to);
 
 __asm__(
   ".text\n"
+#if defined(__thumb__)
+  ".thumb\n"
+#endif
+  ".syntax unified\n"
 #ifdef __APPLE__
   ".globl __mco_switch\n"
+#if defined(__thumb__)
+  ".thumb_func\n"
+#endif
   "__mco_switch:\n"
 #else
   ".globl _mco_switch\n"
-  ".type _mco_switch #function\n"
+  ".type _mco_switch, %function\n"
   ".hidden _mco_switch\n"
+#if defined(__thumb__)
+  ".thumb_func\n"
+#endif
   "_mco_switch:\n"
 #endif
 #ifndef __SOFTFP__
@@ -1132,7 +1142,8 @@ __asm__(
   "  vldmia r1!, {d8-d15}\n"
 #endif
   "  ldr sp, [r1, #9*4]\n"
-  "  ldmia r1, {r4-r11, pc}\n"
+  "  ldmia r1, {r4-r11, lr}\n"
+  "  bx lr\n"
 #ifndef __APPLE__
   ".size _mco_switch, .-_mco_switch\n"
 #endif
@@ -1140,13 +1151,23 @@ __asm__(
 
 __asm__(
   ".text\n"
+#if defined(__thumb__)
+  ".thumb\n"
+#endif
+  ".syntax unified\n"
 #ifdef __APPLE__
   ".globl __mco_wrap_main\n"
+#if defined(__thumb__)
+  ".thumb_func\n"
+#endif
   "__mco_wrap_main:\n"
 #else
   ".globl _mco_wrap_main\n"
-  ".type _mco_wrap_main #function\n"
+  ".type _mco_wrap_main, %function\n"
   ".hidden _mco_wrap_main\n"
+#if defined(__thumb__)
+  ".thumb_func\n"
+#endif
   "_mco_wrap_main:\n"
 #endif
   "  mov r0, r4\n"