diff --git a/src/onigposix.h b/src/onigposix.h
index b42f568c..3514f80e 100644
--- a/src/onigposix.h
+++ b/src/onigposix.h
@@ -74,12 +74,12 @@ extern "C" {
 #define REG_POSIX_ENCODING_UTF16_LE  5
 
 
-typedef int regoff_t;
+typedef int onig_posix_regoff_t;
 
 typedef struct {
-  regoff_t  rm_so;
-  regoff_t  rm_eo;
-} regmatch_t;
+  onig_posix_regoff_t  rm_so;
+  onig_posix_regoff_t  rm_eo;
+} onig_posix_regmatch_t;
 
 /* POSIX regex_t */
 typedef struct {
@@ -161,7 +161,7 @@ ONIG_EXTERN int onig_end P_((void));
 
 
 ONIG_EXTERN int    onig_posix_regcomp P_((onig_posix_regex_t* reg, const char* pat, int options));
-ONIG_EXTERN int    onig_posix_regexec P_((onig_posix_regex_t* reg, const char* str, size_t nmatch, regmatch_t* matches, int options));
+ONIG_EXTERN int    onig_posix_regexec P_((onig_posix_regex_t* reg, const char* str, size_t nmatch, onig_posix_regmatch_t* matches, int options));
 ONIG_EXTERN void   onig_posix_regfree P_((onig_posix_regex_t* reg));
 ONIG_EXTERN size_t onig_posix_regerror P_((int code, const onig_posix_regex_t* reg, char* buf, size_t size));
 
@@ -173,7 +173,9 @@ ONIG_EXTERN int  onig_posix_reg_number_of_names P_((onig_posix_regex_t* reg));
 
 
 /* aliases */
-#define regex_t onig_posix_regex_t
+#define regex_t    onig_posix_regex_t
+#define regmatch_t onig_posix_regmatch_t
+#define regoff_t   onig_posix_regoff_t
 
 #define regcomp  onig_posix_regcomp
 #define regexec  onig_posix_regexec
diff --git a/src/regposerr.c b/src/regposerr.c
index 6ead905a..e5b78992 100644
--- a/src/regposerr.c
+++ b/src/regposerr.c
@@ -38,6 +38,8 @@
 #include "onigposix.h"
 
 #undef regex_t
+#undef regmatch_t
+#undef regoff_t
 #undef regcomp
 #undef regexec
 #undef regfree
diff --git a/src/regposix.c b/src/regposix.c
index 178618d5..87b28195 100644
--- a/src/regposix.c
+++ b/src/regposix.c
@@ -34,6 +34,8 @@
 #include "onigposix.h"
 
 #undef regex_t
+#undef regmatch_t
+#undef regoff_t
 #undef regcomp
 #undef regexec
 #undef regfree
@@ -190,11 +192,11 @@ onig_posix_regcomp(onig_posix_regex_t* reg, const char* pattern, int posix_optio
 
 extern int
 onig_posix_regexec(onig_posix_regex_t* reg, const char* str, size_t nmatch,
-                   regmatch_t pmatch[], int posix_options)
+                   onig_posix_regmatch_t pmatch[], int posix_options)
 {
   int r, i, len;
   UChar* end;
-  regmatch_t* pm;
+  onig_posix_regmatch_t* pm;
   OnigOptionType options;
 
   options = ONIG_OPTION_POSIX_REGION;
@@ -202,11 +204,11 @@ onig_posix_regexec(onig_posix_regex_t* reg, const char* str, size_t nmatch,
   if ((posix_options & REG_NOTEOL) != 0) options |= ONIG_OPTION_NOTEOL;
 
   if (nmatch == 0 || (reg->comp_options & REG_NOSUB) != 0) {
-    pm = (regmatch_t* )NULL;
+    pm = (onig_posix_regmatch_t* )NULL;
     nmatch = 0;
   }
   else if ((int )nmatch < ONIG_C(reg)->num_mem + 1) {
-    pm = (regmatch_t* )xmalloc(sizeof(regmatch_t)
+    pm = (onig_posix_regmatch_t* )xmalloc(sizeof(onig_posix_regmatch_t)
                                * (ONIG_C(reg)->num_mem + 1));
     if (pm == NULL)
       return REG_ESPACE;
@@ -223,7 +225,7 @@ onig_posix_regexec(onig_posix_regex_t* reg, const char* str, size_t nmatch,
   if (r >= 0) {
     r = 0; /* Match */
     if (pm != pmatch && pm != NULL) {
-      xmemcpy(pmatch, pm, sizeof(regmatch_t) * nmatch);
+      xmemcpy(pmatch, pm, sizeof(onig_posix_regmatch_t) * nmatch);
     }
   }
   else if (r == ONIG_MISMATCH) {
@@ -342,7 +344,7 @@ regcomp(onig_posix_regex_t* reg, const char* pattern, int posix_options)
 
 extern int
 regexec(onig_posix_regex_t* reg, const char* str, size_t nmatch,
-        regmatch_t pmatch[], int posix_options)
+        onig_posix_regmatch_t pmatch[], int posix_options)
 {
   return onig_posix_regexec(reg, str, nmatch, pmatch, posix_options);
 }