diff --git a/src/ersky9x/core_cm3.c b/src/ersky9x/core_cm3.c
index eac95e9b5..ad33139f5 100644
--- a/src/ersky9x/core_cm3.c
+++ b/src/ersky9x/core_cm3.c
@@ -760,7 +760,7 @@ uint32_t __STREXB(uint8_t value, uint8_t *addr)
 {
    uint32_t result=0;
 
-   __ASM volatile ("strexb %0, %2, [%1]" : "=r" (result) : "r" (addr), "r" (value) );
+   __ASM volatile ("strexb %0, %2, [%1]" : "=&r" (result) : "r" (addr), "r" (value) );
    return(result);
 }
 
@@ -777,7 +777,7 @@ uint32_t __STREXH(uint16_t value, uint16_t *addr)
 {
    uint32_t result=0;
 
-   __ASM volatile ("strexh %0, %2, [%1]" : "=r" (result) : "r" (addr), "r" (value) );
+   __ASM volatile ("strexh %0, %2, [%1]" : "=&r" (result) : "r" (addr), "r" (value) );
    return(result);
 }