diff --git a/configure.ac b/configure.ac
index ba70973da..a91c26063 100644
--- a/configure.ac
+++ b/configure.ac
@@ -597,6 +597,7 @@ RB_CHK_SYSHEADER(codecvt, [CODECVT])
 RB_CHK_SYSHEADER(sstream, [SSTREAM])
 RB_CHK_SYSHEADER(fstream, [FSTREAM])
 RB_CHK_SYSHEADER(iostream, [IOSTREAM])
+RB_CHK_SYSHEADER(iosfwd, [IOSFWD])
 RB_CHK_SYSHEADER(iomanip, [IOMANIP])
 RB_CHK_SYSHEADER(cstdio, [CSTDIO])
 RB_CHK_SYSHEADER(chrono, [CHRONO])