diff --git a/configure.ac b/configure.ac
index 5b18fd34..75425464 100644
--- a/configure.ac
+++ b/configure.ac
@@ -760,6 +760,15 @@ case "${host}" in
 	AC_DEFINE([JEMALLOC_THREADED_INIT], [ ], [ ])
 	AC_DEFINE([JEMALLOC_USE_CXX_THROW], [ ], [ ])
 	;;
+  *-*-gnu*)
+	dnl syscall(2) and secure_getenv(3) are exposed by _GNU_SOURCE.
+	JE_APPEND_VS(CPPFLAGS, -D_GNU_SOURCE)
+	JE_APPEND_VS(CPPFLAGS, -DPATH_MAX=8192)
+	abi="elf"
+	AC_DEFINE([JEMALLOC_HAS_ALLOCA_H])
+	AC_DEFINE([JEMALLOC_THREADED_INIT], [ ])
+	AC_DEFINE([JEMALLOC_USE_CXX_THROW], [ ])
+	;;
   *-*-netbsd*)
 	AC_MSG_CHECKING([ABI])
         AC_COMPILE_IFELSE([AC_LANG_PROGRAM(