Fix C-ABI breakage

Re-export missing C memory handling functions.

Task-number: QTBUG-61521
Change-Id: I8f94d93a70c81117735a9610e391a1e31c54f15a
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

src/core/api/core_api.pro

@@ -50,6 +50,8 @@ SOURCES = \
     qwebengineurlrequestjob.cpp \
     qwebengineurlschemehandler.cpp
 
+### Qt6 Remove this workaround
 unix:!isEmpty(QMAKE_LFLAGS_VERSION_SCRIPT):!static {
-    SOURCES += qtbug-60565.cpp
+    SOURCES += qtbug-60565.cpp \
+               qtbug-61521.cpp
 }

src/core/api/qtbug-61521.cpp

@@ -0,0 +1,121 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <stdlib.h>
+#include <malloc.h>
+
+#define SHIM_ALIAS_SYMBOL(fn) __attribute__((weak, alias(#fn)))
+#define SHIM_SYMBOL_VERSION(fn) __asm__(".symver __" #fn "," #fn "@Qt_5")
+#define SHIM_HIDDEN __attribute__ ((visibility ("hidden")))
+
+extern "C" {
+
+SHIM_SYMBOL_VERSION(malloc);
+void* __malloc(size_t size)
+    SHIM_ALIAS_SYMBOL(ShimMalloc);
+
+SHIM_SYMBOL_VERSION(free);
+void __free(void* ptr)
+    SHIM_ALIAS_SYMBOL(ShimFree);
+
+SHIM_SYMBOL_VERSION(realloc);
+void* __realloc(void* ptr, size_t size)
+    SHIM_ALIAS_SYMBOL(ShimRealloc);
+
+SHIM_SYMBOL_VERSION(calloc);
+void* __calloc(size_t n, size_t size)
+    SHIM_ALIAS_SYMBOL(ShimCalloc);
+
+SHIM_SYMBOL_VERSION(cfree);
+void __cfree(void* ptr)
+    SHIM_ALIAS_SYMBOL(ShimCFree);
+
+SHIM_SYMBOL_VERSION(memalign);
+void* __memalign(size_t align, size_t s)
+    SHIM_ALIAS_SYMBOL(ShimMemalign);
+
+SHIM_SYMBOL_VERSION(valloc);
+void* __valloc(size_t size)
+    SHIM_ALIAS_SYMBOL(ShimValloc);
+
+SHIM_SYMBOL_VERSION(pvalloc);
+void* __pvalloc(size_t size)
+    SHIM_ALIAS_SYMBOL(ShimPvalloc);
+
+SHIM_SYMBOL_VERSION(posix_memalign);
+int __posix_memalign(void** r, size_t a, size_t s)
+    SHIM_ALIAS_SYMBOL(ShimPosixMemalign);
+
+SHIM_HIDDEN void* ShimMalloc(size_t size) {
+    return malloc(size);
+}
+
+SHIM_HIDDEN void ShimFree(void* ptr) {
+    free(ptr);
+}
+
+SHIM_HIDDEN void* ShimRealloc(void* ptr, size_t size) {
+    return realloc(ptr,size);
+}
+
+SHIM_HIDDEN void* ShimCalloc(size_t n, size_t size) {
+    return calloc(n,size);
+}
+
+SHIM_HIDDEN void ShimCFree(void* ptr) {
+    cfree(ptr);
+}
+
+SHIM_HIDDEN void* ShimMemalign(size_t align, size_t s) {
+    return memalign(align,s);
+}
+
+SHIM_HIDDEN void* ShimValloc(size_t size) {
+    return  valloc(size);
+}
+
+SHIM_HIDDEN void* ShimPvalloc(size_t size) {
+    return pvalloc(size);
+}
+
+SHIM_HIDDEN int ShimPosixMemalign(void** r, size_t a, size_t s) {
+    return posix_memalign(r,a,s);
+}
+}  // extern "C"