diff --git a/include/mimalloc-internal.h b/include/mimalloc-internal.h
index 145f6f92..c0fa1d66 100644
--- a/include/mimalloc-internal.h
+++ b/include/mimalloc-internal.h
@@ -699,6 +699,8 @@ static inline void* mi_tls_slot(size_t slot) mi_attr_noexcept {
   __asm__("movl %%gs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // 32-bit always uses GS
 #elif defined(__MACH__) && defined(__x86_64__)
   __asm__("movq %%gs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // x86_64 macOSX uses GS
+#elif defined(__x86_64__) && (MI_INTPTR_SIZE==4)
+  __asm__("movl %%fs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // x32 ABI
 #elif defined(__x86_64__)
   __asm__("movq %%fs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // x86_64 Linux, BSD uses FS
 #elif defined(__arm__)
@@ -720,6 +722,8 @@ static inline void mi_tls_slot_set(size_t slot, void* value) mi_attr_noexcept {
   __asm__("movl %1,%%gs:%0" : "=m" (*((void**)ofs)) : "rn" (value) : );  // 32-bit always uses GS
 #elif defined(__MACH__) && defined(__x86_64__)
   __asm__("movq %1,%%gs:%0" : "=m" (*((void**)ofs)) : "rn" (value) : );  // x86_64 macOSX uses GS
+#elif defined(__x86_64__) && (MI_INTPTR_SIZE==4)
+  __asm__("movl %1,%%fs:%1" : "=m" (*((void**)ofs)) : "rn" (value) : );  // x32 ABI
 #elif defined(__x86_64__)
   __asm__("movq %1,%%fs:%1" : "=m" (*((void**)ofs)) : "rn" (value) : );  // x86_64 Linux, BSD uses FS
 #elif defined(__arm__)