diff -r 99a34860c105 -r d938228c382e src/ucx/compare.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ucx/compare.c	Sun Nov 06 15:53:32 2022 +0100
@@ -0,0 +1,182 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "cx/compare.h"
+
+#include <stdint.h>
+#include <math.h>
+
+int cx_cmp_int(void const *i1, void const *i2) {
+    int a = *((const int*) i1);
+    int b = *((const int*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_longint(void const *i1, void const *i2) {
+    long int a = *((const long int*) i1);
+    long int b = *((const long int*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_longlong(void const *i1, void const *i2) {
+    long long a = *((const long long*) i1);
+    long long b = *((const long long*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_int16(void const *i1, void const *i2) {
+    int16_t a = *((const int16_t*) i1);
+    int16_t b = *((const int16_t*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_int32(void const *i1, void const *i2) {
+    int32_t a = *((const int32_t*) i1);
+    int32_t b = *((const int32_t*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_int64(void const *i1, void const *i2) {
+    int64_t a = *((const int64_t*) i1);
+    int64_t b = *((const int64_t*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_uint(void const *i1, void const *i2) {
+    unsigned int a = *((const unsigned int*) i1);
+    unsigned int b = *((const unsigned int*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_ulongint(void const *i1, void const *i2) {
+    unsigned long int a = *((const unsigned long int*) i1);
+    unsigned long int b = *((const unsigned long int*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_ulonglong(void const *i1, void const *i2) {
+    unsigned long long a = *((const unsigned long long*) i1);
+    unsigned long long b = *((const unsigned long long*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_uint16(void const *i1, void const *i2) {
+    uint16_t a = *((const uint16_t*) i1);
+    uint16_t b = *((const uint16_t*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_uint32(void const *i1, void const *i2) {
+    uint32_t a = *((const uint32_t*) i1);
+    uint32_t b = *((const uint32_t*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_uint64(void const *i1, void const *i2) {
+    uint64_t a = *((const uint64_t*) i1);
+    uint64_t b = *((const uint64_t*) i2);
+    if (a == b) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_float(void const *f1, void const *f2) {
+    float a = *((const float*) f1);
+    float b = *((const float*) f2);
+    if (fabsf(a - b) < 1e-6f) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_double(void const *d1, void const *d2) {
+    double a = *((const double*) d1);
+    double b = *((const double*) d2);
+    if (fabs(a - b) < 1e-14) {
+        return 0;
+    } else {
+        return a < b ? -1 : 1;
+    }
+}
+
+int cx_cmp_ptr(void const *ptr1, void const *ptr2) {
+    const intptr_t p1 = (const intptr_t) ptr1;
+    const intptr_t p2 = (const intptr_t) ptr2;
+    if (p1 == p2) {
+        return 0;
+    } else {
+        return p1  < p2 ? -1 : 1;
+    }
+}