diff --git a/libc/bionic/sysconf.cpp b/libc/bionic/sysconf.cpp
index 951860d48..fb704ad1e 100644
--- a/libc/bionic/sysconf.cpp
+++ b/libc/bionic/sysconf.cpp
@@ -149,7 +149,7 @@ static int __sysconf_monotonic_clock() {
   return (rc == -1) ? -1 : _POSIX_VERSION;
 }
 
-int sysconf(int name) {
+long sysconf(int name) {
   switch (name) {
     case _SC_ARG_MAX:           return _POSIX_ARG_MAX;
     case _SC_CHILD_MAX:         return CHILD_MAX;
diff --git a/libc/include/sys/sysconf.h b/libc/include/sys/sysconf.h
index 0a46e7aab..3d058d748 100644
--- a/libc/include/sys/sysconf.h
+++ b/libc/include/sys/sysconf.h
@@ -129,7 +129,7 @@ __BEGIN_DECLS
 #define _SC_AVPHYS_PAGES                0x0063
 #define _SC_MONOTONIC_CLOCK             0x0064
 
-extern int sysconf(int name);
+long sysconf(int);
 
 __END_DECLS
 
diff --git a/libc/include/unistd.h b/libc/include/unistd.h
index dca9b3da9..e94ee66fb 100644
--- a/libc/include/unistd.h
+++ b/libc/include/unistd.h
@@ -202,7 +202,7 @@ extern int  acct(const char*  filepath);
 
 int getpagesize(void);
 
-extern int sysconf(int  name);
+long sysconf(int);
 
 extern int daemon(int, int);