third_party/qemu/patches/fix_code_issues.patch

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From 402ac3cc59ef115c41eee0f1dca3b1c4b30d6baa Mon Sep 17 00:00:00 2001
From: Lorenz Brun <lorenz@brun.one>
Date: Wed, 10 Mar 2021 17:55:55 +0100
Subject: [PATCH] Fix QEMU code issues
Company: nexantic GmbH

---
 qom/object.c      |  2 +-
 softmmu/physmem.c | 15 ++++++++++++++-
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/qom/object.c b/qom/object.c
index 1065355233..f3aa56cc52 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -692,7 +692,7 @@ static void object_finalize(void *data)
 
 /* Find the minimum alignment guaranteed by the system malloc. */
 #if __STDC_VERSION__ >= 201112L
-typddef max_align_t qemu_max_align_t;
+typedef max_align_t qemu_max_align_t;
 #else
 typedef union {
     long l;
diff --git a/softmmu/physmem.c b/softmmu/physmem.c
index 3027747c03..f5bbdd7e2d 100644
--- a/softmmu/physmem.c
+++ b/softmmu/physmem.c
@@ -2675,7 +2675,20 @@ static void invalidate_and_set_dirty(MemoryRegion *mr, hwaddr addr,
     }
     if (dirty_log_mask & (1 << DIRTY_MEMORY_CODE)) {
         assert(tcg_enabled());
-        tb_invalidate_phys_range(addr, addr + length);
+        // Metropolis does not link against TCG (Tiny Code Generator, qemu's
+        // software recompilation backend), where tb_invalidate_phys_range is
+        // implemented. Because we do not enable TCG at all, this branch should
+        // never be taken, and even if it is taken, the assert above should
+        // file aborting execution. 
+        // Ideally, all compilers would use the above data to elide the call to
+        // tb_invalidate_phys_range and everything would be fine, but that's
+        // unfortunately not the case, at least within Metropolis' build. Thus,
+        // in order to prevent the compiler from spuriously linking against a
+        // symbol that we do not compile, we comment the call out, and add
+        // another assert that will always fire, to truly make sure that this
+        // branch never gets taken in practice.
+        assert(0);
+        // tb_invalidate_phys_range(addr, addr + length);
         dirty_log_mask &= ~(1 << DIRTY_MEMORY_CODE);
     }
     cpu_physical_memory_set_dirty_range(addr, length, dirty_log_mask);
-- 
2.26.3