Qt 5.15 patch

0001-qsimd-Workaround-32bits-MinGW-compiler-bug.patch

From c01763ea13416e974fa438a972c9739d5abb8ec3 Mon Sep 17 00:00:00 2001
From: Johannes Kauffmann <[email protected]>
Date: Tue, 11 Oct 2022 23:06:28 +0200
Subject: [PATCH] qsimd: Workaround 32bits MinGW compiler bug

GCC PR 58372 [1] causes ICE compiling qsimd.cpp on 32bits MinGW. Work
around this by detecting 32bits MinGW on the affected GCC versions:
GCC <= 7.3.0 and GCC <= 8.2.0 on 8.x.

The wiki [2] lists i686-8.1.0-release-posix-dwarf-rt_v6-rev0 as a
reference configuration for Qt 5.15, so someone could easily bump into
this when compiling 5.15 for 32bits on debug configuration.

[1]. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58372
[2]. https://wiki.qt.io/MinGW

Fixes: QTBUG-70487
---
 src/corelib/tools/qsimd.cpp |  2 +-
 src/corelib/tools/qsimd_p.h | 19 ++++++++++++++++++-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/corelib/tools/qsimd.cpp b/src/corelib/tools/qsimd.cpp
index 798ac93ad2..08c34a2b83 100644
--- a/src/corelib/tools/qsimd.cpp
+++ b/src/corelib/tools/qsimd.cpp
@@ -598,7 +598,7 @@ void qDumpCPUFeatures()
     puts("");
 }
 
-#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
+#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND) && !QTBUG_70487
 
 #  ifdef Q_PROCESSOR_X86_64
 #    define _rdrandXX_step _rdrand64_step
diff --git a/src/corelib/tools/qsimd_p.h b/src/corelib/tools/qsimd_p.h
index 26e98c4542..b3405b0af9 100644
--- a/src/corelib/tools/qsimd_p.h
+++ b/src/corelib/tools/qsimd_p.h
@@ -346,7 +346,24 @@ extern Q_CORE_EXPORT QBasicAtomicInteger<unsigned> qt_cpu_features[2];
 #endif
 Q_CORE_EXPORT quint64 qDetectCpuFeatures();
 
-#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND) && !defined(QT_BOOTSTRAPPED)
+/*
+ * Work around GCC PR 58372, causing ICE when compiling qsimd.cpp
+ * on MinGW32 or MinGW-w64 targeting 32bits.
+ *
+ * It affects GCC <= 7.3.0 for 7.x and GCC <= 8.2.0 for 8.x.
+ * It is fixed completely for GCC 9 and beyond [1].
+ *
+ * [1]. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58372
+ */
+#if defined(Q_CC_GNU) && !defined(__clang__) &&             /* Clang disguises as GCC */                     \
+    defined(__MINGW32__) && defined(__MINGW64__) &&         /* MinGW32 or MinGW-w64 targeting 32bit only */  \
+    (Q_CC_GNU < 704 || (Q_CC_GNU >= 800 && Q_CC_GNU < 803)) /* affected GCC versions */
+# define QTBUG_70487 1
+#else
+# define QTBUG_70487 0
+#endif
+
+#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND) && !defined(QT_BOOTSTRAPPED) && !QTBUG_70487
 Q_CORE_EXPORT qsizetype qRandomCpu(void *, qsizetype) noexcept;
 #else
 static inline qsizetype qRandomCpu(void *, qsizetype) noexcept
-- 
2.38.0.windows.1