Allow verifying _REENT_CHECK macros memory allocation

- change sys/reent.h to replace _REENT_CHECK_DEBUG with
  _REENT_CHECK_VERIFY which when set asserts that any memory
  allocated is non-NULL and calls __assert_func directly
- add new --enable-newlib-reent-check-verify configure option
- add support for configure.host to specify default for
  newlib_reent_check_verify
- add _REENT_CHECK_VERIFY macro support to acconfig.h and newlib.hin

newlib/acconfig.h

@@ -26,6 +26,9 @@
    very restricted storage.  */
 #undef _WANT_REENT_SMALL
 
+/* Verify _REENT_CHECK macros allocate memory successfully. */
+#undef _REENT_CHECK_VERIFY
+
 /* Multibyte supported */
 #undef _MB_CAPABLE
 

newlib/configure

@@ -788,6 +788,7 @@ enable_newlib_register_fini
 enable_newlib_io_long_long
 enable_newlib_io_long_double
 enable_newlib_mb
+enable_newlib_reent_check_verify
 enable_newlib_iconv_encodings
 enable_newlib_iconv_from_encodings
 enable_newlib_iconv_to_encodings
@@ -1463,6 +1464,7 @@ Optional Features:
   --enable-newlib-io-long-long   enable long long type support in IO functions like printf/scanf
   --enable-newlib-io-long-double   enable long double type support in IO functions printf/scanf
   --enable-newlib-mb        enable multibyte support
+  --enable-newlib-reent-check-verify        enable checking of _REENT_CHECK memory allocation
   --enable-newlib-iconv-encodings   enable specific comma-separated list of bidirectional iconv encodings to be built-in
   --enable-newlib-iconv-from-encodings   enable specific comma-separated list of \"from\" iconv encodings to be built-in
   --enable-newlib-iconv-to-encodings   enable specific comma-separated list of \"to\" iconv encodings to be built-in
@@ -2310,6 +2312,17 @@ else
   newlib_mb=
 fi
 
+# Check whether --enable-newlib-reent-check-verify was given.
+if test "${enable_newlib_reent_check_verify+set}" = set; then :
+  enableval=$enable_newlib_reent_check_verify; case "${enableval}" in
+  yes) newlib_reent_check_verify=yes;;
+  no)  newlib_reent_check_verify=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-reent-check-verify option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_reent_check_verify=
+fi
+
 # Check whether --enable-newlib-iconv-encodings was given.
 if test "${enable_newlib_iconv_encodings+set}" = set; then :
   enableval=$enable_newlib_iconv_encodings; if test x${enableval} = x; then
@@ -11840,7 +11853,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11843 "configure"
+#line 11856 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11946,7 +11959,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11949 "configure"
+#line 11962 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12351,6 +12364,13 @@ _ACEOF
 
 fi
 
+if test "${newlib_reent_check_verify}" = "yes"; then
+cat >>confdefs.h <<_ACEOF
+#define _REENT_CHECK_VERIFY 1
+_ACEOF
+
+fi
+
 if test "${newlib_io_c99_formats}" = "yes"; then
 cat >>confdefs.h <<_ACEOF
 #define _WANT_IO_C99_FORMATS 1

newlib/configure.host

@@ -29,6 +29,7 @@
 #   newlib_io_long_double --enable-newlib-io-long-double ("yes", "no", "")
 #   newlib_global_stdio_streams --enable-global-stdio-streams ("yes", "no, "")
 #   newlib_fno_builtin  --disable-newlib-fno-builtin ("yes", "no, "")
+#   newlib_reent_check_verify  --enable-newlib-reent-check-verify ("yes", "no, "")
 
 # It sets the following shell variables:
 #   newlib_cflags	Special CFLAGS to use when building
@@ -76,6 +77,7 @@ default_newlib_io_long_double=no
 default_newlib_io_pos_args=no
 default_newlib_atexit_dynamic_alloc=yes
 default_newlib_nano_malloc=no
+default_newlib_reent_check_verify=no
 aext=a
 oext=o
 lpfx="lib_a-"
@@ -952,6 +954,13 @@ if [ "x${newlib_nano_malloc}" = "x" ]; then
 	fi
 fi
 
+# Enable _REENT_CHECK macro memory allocation verification.
+if [ "x${newlib_reent_check_verify}" = "x" ]; then
+	if [ ${default_newlib_reent_check_verify} = "yes" ]; then
+		newlib_reent_check_verify="yes";
+	fi
+fi
+
 # Remove rpc headers if xdr_dir not specified
 if [ "x${xdr_dir}" = "x" ]; then
 	noinclude="${noinclude} rpc/types.h rpc/xdr.h"

newlib/configure.in

@@ -66,6 +66,16 @@ AC_ARG_ENABLE(newlib-mb,
   *)   AC_MSG_ERROR(bad value ${enableval} for newlib-mb option) ;;
  esac], [newlib_mb=])dnl
 
+dnl Enable verification of successful memory allocation for _REENT_CHECK family of macros
+dnl Support --enable-newlib-reent-check-verify
+AC_ARG_ENABLE(newlib-reent-check-verify,
+[  --enable-newlib-reent-check-verify        enable checking of _REENT_CHECK memory allocation],
+[case "${enableval}" in
+  yes) newlib_reent_check_verify=yes;;
+  no)  newlib_reent_check_verify=no ;;
+  *)   AC_MSG_ERROR(bad value ${enableval} for newlib-reent-check-verify option) ;;
+ esac], [newlib_reent_check_verify=])dnl
+
 dnl Support --enable-newlib-iconv-encodings
 AC_ARG_ENABLE(newlib-iconv-encodings,
 [  --enable-newlib-iconv-encodings   enable specific comma-separated list of bidirectional iconv encodings to be built-in],
@@ -396,6 +406,10 @@ if test "${newlib_elix_level}" -gt "0"; then
 AC_DEFINE_UNQUOTED(_ELIX_LEVEL,${newlib_elix_level})
 fi
 
+if test "${newlib_reent_check_verify}" = "yes"; then
+AC_DEFINE_UNQUOTED(_REENT_CHECK_VERIFY)
+fi
+
 if test "${newlib_io_c99_formats}" = "yes"; then
 AC_DEFINE_UNQUOTED(_WANT_IO_C99_FORMATS)
 fi

newlib/libc/include/sys/reent.h

@@ -498,10 +498,10 @@ extern const struct __sFILE_fake __sf_fake_stderr;
 
 #endif /* _REENT_GLOBAL_STDIO_STREAMS */
 
-/* Only add assert() calls if we are specified to debug.  */
-#ifdef _REENT_CHECK_DEBUG
+/* Specify how to handle reent_check malloc failures. */
+#ifdef _REENT_CHECK_VERIFY
 #include <assert.h>
-#define __reent_assert(x) assert(x)
+#define __reent_assert(x) ((x) ? (void)0 : __assert_func(__FILE__, __LINE__, (char *)0, "REENT malloc succeeded"))
 #else
 #define __reent_assert(x) ((void)0)
 #endif

newlib/newlib.hin

@@ -32,6 +32,9 @@
    very restricted storage.  */
 #undef _WANT_REENT_SMALL
 
+/* Verify _REENT_CHECK macros allocate memory successfully. */
+#undef _REENT_CHECK_VERIFY
+
 /* Multibyte supported */
 #undef _MB_CAPABLE