From cdcb75c46b968dbfeb1992c6bee19aceda27da38 Mon Sep 17 00:00:00 2001
From: Thiago Macieira <thiago.macieira@intel.com>
Date: Tue, 26 May 2020 09:14:15 -0700
Subject: [PATCH] QMimeDatabase/zlib: fix build with z_const macro empty

The next_in pointer in z_stream is defined as "z_const Bytef *" but
z_const is actually an empty macro in most builds. Since our data is
read-only constexpr, we need this const_cast to compile.

Fixes: QTBUG-84457
Pick-to: 5.15
Change-Id: Ied637aece2a7427b8a2dfffd1612a01ae46f7c1a
Reviewed-by: David Faure <david.faure@kdab.com>
---
 src/corelib/mimetypes/qmimeprovider.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/corelib/mimetypes/qmimeprovider.cpp b/src/corelib/mimetypes/qmimeprovider.cpp
index cbf25625816..47b5e421672 100644
--- a/src/corelib/mimetypes/qmimeprovider.cpp
+++ b/src/corelib/mimetypes/qmimeprovider.cpp
@@ -647,7 +647,7 @@ QMimeXMLProvider::QMimeXMLProvider(QMimeDatabasePrivate *db, InternalDatabaseEnu
 #elif defined(MIME_DATABASE_IS_GZIP)
     std::unique_ptr<char []> uncompressed(new char[size]);
     z_stream zs = {};
-    zs.next_in = mimetype_database;
+    zs.next_in = const_cast<Bytef *>(mimetype_database);
     zs.avail_in = sizeof(mimetype_database);
     zs.next_out = reinterpret_cast<Bytef *>(uncompressed.get());
     zs.avail_out = size;