test-json: check absolute and relative difference in floating point test

The test fails under valgrind, so there was an exception for valgrind.
Unfortunately that check only works when valgrind-devel headers are
available during build. But it is possible to have just valgrind installed,
or simply install it after the build, and then "valgrind test-json" would
fail.

It also seems that even without valgrind, this fails on some arm32 CPUs.
Let's do the usual-style test for absolute and relative differences.

diff --git a/src/test/test-json.c b/src/test/test-json.c
index 5aa4d19dbec499388c43f805e34850998b2d171a..cd6269f798f5b8f387a9f175260dc78e69c4123d 100644 (file)
--- a/src/test/test-json.c
+++ b/src/test/test-json.c
@@ -1,9 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1+ */
 
 #include <math.h>
-#if HAVE_VALGRIND_VALGRIND_H
-#include <valgrind/valgrind.h>
-#endif
 
 #include "alloc-util.h"
 #include "fd-util.h"
@@ -45,12 +42,13 @@ static void test_tokenizer(const char *data, ...) {
 
                         d = va_arg(ap, long double);
 
-#if HAVE_VALGRIND_VALGRIND_H
-                        if (!RUNNING_ON_VALGRIND)
-#endif
-                                /* Valgrind doesn't support long double calculations and automatically downgrades to 80bit:
-                                 * http://www.valgrind.org/docs/manual/manual-core.html#manual-core.limits */
-                                assert_se(fabsl(d - v.real) < 0.001L);
+                        /* Valgrind doesn't support long double calculations and automatically downgrades to 80bit:
+                         * http://www.valgrind.org/docs/manual/manual-core.html#manual-core.limits.
+                         * Some architectures might not support long double either.
+                         */
+
+                        assert_se(fabsl(d - v.real) < 1e-10 ||
+                                  fabsl((d - v.real) / v.real) < 1e-10);
 
                 } else if (t == JSON_TOKEN_INTEGER) {
                         intmax_t i;