diff --git a/Makefile.am b/Makefile.am
index 159e22a7..0cc47b69 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -12,7 +12,7 @@ applications_DATA = htop.desktop
 pixmapdir = $(datadir)/pixmaps
 pixmap_DATA = htop.png
 
-AM_CFLAGS = -pedantic -Wall $(wextra_flag) -std=c99 -D_XOPEN_SOURCE_EXTENDED -DSYSCONFDIR=\"$(sysconfdir)\" -I"$(top_srcdir)/$(my_htop_platform)"
+AM_CFLAGS += -pedantic -Wall $(wextra_flag) -std=c99 -D_XOPEN_SOURCE_EXTENDED -DSYSCONFDIR=\"$(sysconfdir)\" -I"$(top_srcdir)/$(my_htop_platform)"
 AM_LDFLAGS =
 AM_CPPFLAGS = -DNDEBUG
 
diff --git a/configure.ac b/configure.ac
index 71a4f799..4e357a31 100644
--- a/configure.ac
+++ b/configure.ac
@@ -295,6 +295,9 @@ then
    ])
 fi
 
+AC_ARG_ENABLE([werror], [AS_HELP_STRING([--enable-werror], [Treat warnings as errors (default: warnings are not errors)])], [enable_werror="$enableval"], [enable_werror=no])
+AS_IF([test "x$enable_werror" = "xyes"], [AM_CFLAGS="$AM_CFLAGS -Werror"])
+AC_SUBST([AM_CFLAGS])
 
 # Bail out on errors.
 # ----------------------------------------------------------------------