diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index 5583ef2..c5c0a12 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -826,6 +826,11 @@
 
 PERL_EXE = $(PERL)\Bin$(PERL_ARCH)\perl
 PERL_INC = /I $(PERL_INCDIR)
+!if $(MSVC_MAJOR) <= 11
+# ActivePerl 5.20+ requires stdbool.h but VC2012 or earlier doesn't have it.
+# Use a stub stdbool.h.
+PERL_INC = $(PERL_INC) /I if_perl_msvc
+!endif
 PERL_OBJ = $(OUTDIR)\if_perl.obj $(OUTDIR)\if_perlsfio.obj
 XSUBPP = $(PERL)\lib\ExtUtils\xsubpp
 !if exist($(XSUBPP))
diff --git a/src/if_perl_msvc/stdbool.h b/src/if_perl_msvc/stdbool.h
new file mode 100644
index 0000000..de89e3b
--- /dev/null
+++ b/src/if_perl_msvc/stdbool.h
@@ -0,0 +1,3 @@
+/* A stub stdbool.h for VC2012 or earlier.
+ * ActivePerl 5.20+ requires stdbool.h but VC2012 doesn't have it. */
+#define bool char
diff --git a/src/version.c b/src/version.c
index 59f9bc0..4023711 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1011,
+/**/
     1010,
 /**/
     1009,