diff --git a/configure.ac b/configure.ac
index 8ba165a4..fe2d6327 100644
--- a/configure.ac
+++ b/configure.ac
@@ -27,7 +27,6 @@ AM_PROG_CC_C_O
 CC_CHECK_CFLAGS_APPEND([-Wall])
 CC_CHECK_CFLAGS_APPEND([-Wextra])
 CC_CHECK_CFLAGS_APPEND([-Wno-unused-parameter])
-CC_CHECK_CFLAGS_APPEND([-Wno-dollar-in-identifier-extension])
 # AM_PROG_AR is not available in automake v0.11 but it's essential in v0.12.
 m4_ifdef([AM_PROG_AR], [AM_PROG_AR])
 # autoconf complains if AC_PROG_LIBTOOL precedes AM_PROG_AR.