diff --git a/lib/libc/alpha/sys/Makefile.inc b/lib/libc/alpha/sys/Makefile.inc
index 33107e55f05e..b03490085182 100644
--- a/lib/libc/alpha/sys/Makefile.inc
+++ b/lib/libc/alpha/sys/Makefile.inc
@@ -12,6 +12,6 @@ NOASM=	__semctl.o break.o exit.o ftruncate.o getdomainname.o getlogin.o \
 
 PSEUDO=	_getlogin.o
 
-# Pseudo syscalls that are renamed as _thread_sys_{pseudo} when
-# building libc_r.
+# Pseudo syscalls that are renamed as __sys_{pseudo} so that libc_r
+# can override them with replacements.
 PSEUDOR= _exit.o
diff --git a/lib/libc/amd64/sys/Makefile.inc b/lib/libc/amd64/sys/Makefile.inc
index c73948d2d22e..4a6087506090 100644
--- a/lib/libc/amd64/sys/Makefile.inc
+++ b/lib/libc/amd64/sys/Makefile.inc
@@ -16,8 +16,8 @@ NOASM=	__semctl.o break.o exit.o ftruncate.o getdomainname.o getlogin.o \
 
 PSEUDO=	_getlogin.o
 
-# Pseudo syscalls that are renamed as _thread_sys_{pseudo} when
-# building libc_r.
+# Pseudo syscalls that are renamed as __sys_{pseudo} so that libc_r can
+# override them with replacements.
 PSEUDOR=	_exit.o
 
 .if ${LIB} == "c"
diff --git a/lib/libc/i386/sys/Makefile.inc b/lib/libc/i386/sys/Makefile.inc
index c73948d2d22e..4a6087506090 100644
--- a/lib/libc/i386/sys/Makefile.inc
+++ b/lib/libc/i386/sys/Makefile.inc
@@ -16,8 +16,8 @@ NOASM=	__semctl.o break.o exit.o ftruncate.o getdomainname.o getlogin.o \
 
 PSEUDO=	_getlogin.o
 
-# Pseudo syscalls that are renamed as _thread_sys_{pseudo} when
-# building libc_r.
+# Pseudo syscalls that are renamed as __sys_{pseudo} so that libc_r can
+# override them with replacements.
 PSEUDOR=	_exit.o
 
 .if ${LIB} == "c"
diff --git a/lib/libc/ia64/sys/Makefile.inc b/lib/libc/ia64/sys/Makefile.inc
index 33107e55f05e..b03490085182 100644
--- a/lib/libc/ia64/sys/Makefile.inc
+++ b/lib/libc/ia64/sys/Makefile.inc
@@ -12,6 +12,6 @@ NOASM=	__semctl.o break.o exit.o ftruncate.o getdomainname.o getlogin.o \
 
 PSEUDO=	_getlogin.o
 
-# Pseudo syscalls that are renamed as _thread_sys_{pseudo} when
-# building libc_r.
+# Pseudo syscalls that are renamed as __sys_{pseudo} so that libc_r
+# can override them with replacements.
 PSEUDOR= _exit.o