check if shmat is available to use afl

* Android has sys/shm.h but doesn't have shmat

configure

@@ -12998,13 +12998,6 @@ if test "x$ac_cv_header_stdint_h" = xyes; then :
 fi
 
 
-ac_fn_c_check_header_mongrel "$LINENO" "sys/shm.h" "ac_cv_header_sys_shm_h" "$ac_includes_default"
-if test "x$ac_cv_header_sys_shm_h" = xyes; then :
-  $as_echo "#define HAS_SYS_SHM_H 1" >>confdefs.h
-
-fi
-
-
 ac_fn_c_check_header_compile "$LINENO" "dirent.h" "ac_cv_header_dirent_h" "#include <sys/types.h>
 "
 if test "x$ac_cv_header_dirent_h" = xyes; then :
@@ -15604,6 +15597,23 @@ if test "x$ac_cv_func_getauxval" = xyes; then :
 fi
 
 
+## shmat
+ac_fn_c_check_header_mongrel "$LINENO" "sys/shm.h" "ac_cv_header_sys_shm_h" "$ac_includes_default"
+if test "x$ac_cv_header_sys_shm_h" = xyes; then :
+
+    $as_echo "#define HAS_SYS_SHM_H 1" >>confdefs.h
+
+    ac_fn_c_check_func "$LINENO" "shmat" "ac_cv_func_shmat"
+if test "x$ac_cv_func_shmat" = xyes; then :
+  $as_echo "#define HAS_SHMAT 1" >>confdefs.h
+
+fi
+
+
+fi
+
+
+
 ## execvpe
 
 ac_fn_c_check_func "$LINENO" "execvpe" "ac_cv_func_execvpe"

configure.ac

@@ -740,7 +740,6 @@ AS_IF([test "x$ac_cv_lib_m_cos" = xyes ], [mathlib="-lm"], [mathlib=""])
 AC_CHECK_HEADER([math.h])
 AC_CHECK_HEADERS([unistd.h],[AC_DEFINE([HAS_UNISTD])])
 AC_CHECK_HEADER([stdint.h],[AC_DEFINE([HAS_STDINT_H])])
-AC_CHECK_HEADER([sys/shm.h],[AC_DEFINE([HAS_SYS_SHM_H])])
 AC_CHECK_HEADER([dirent.h], [AC_DEFINE([HAS_DIRENT])], [],
   [#include <sys/types.h>])
 
@@ -1564,6 +1563,13 @@ AC_CHECK_FUNC([accept4], [AC_DEFINE([HAS_ACCEPT4])])
 
 AC_CHECK_FUNC([getauxval], [AC_DEFINE([HAS_GETAUXVAL])])
 
+## shmat
+AC_CHECK_HEADER([sys/shm.h],
+  [
+    AC_DEFINE([HAS_SYS_SHM_H])
+    AC_CHECK_FUNC([shmat], [AC_DEFINE([HAS_SHMAT])])
+  ])
+
 ## execvpe
 
 AC_CHECK_FUNC([execvpe], [AC_DEFINE([HAS_EXECVPE])])

runtime/afl.c

@@ -15,7 +15,7 @@
 /* Runtime support for afl-fuzz */
 #include "caml/config.h"
 
-#if !defined(HAS_SYS_SHM_H)
+#if !defined(HAS_SYS_SHM_H) || !defined(HAS_SHMAT)
 
 #include "caml/mlvalues.h"
 

runtime/caml/s.h.in

@@ -245,6 +245,8 @@
 
 #undef HAS_SYS_SHM_H
 
+#undef HAS_SHMAT
+
 #undef HAS_EXECVPE
 
 #undef HAS_POSIX_SPAWN