From 1f739fa4e49839c63ef2831ed454965746ed104d Mon Sep 17 00:00:00 2001
From: Marian Buschsieweke <marian.buschsieweke@ovgu.de>
Date: Sat, 13 Nov 2021 09:17:04 +0100
Subject: [PATCH] Silence -Wcast-align in public headers

---
 include/flatbuffers/flatbuffers.h | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/include/flatbuffers/flatbuffers.h b/include/flatbuffers/flatbuffers.h
index a1a95f00..8c50576e 100644
--- a/include/flatbuffers/flatbuffers.h
+++ b/include/flatbuffers/flatbuffers.h
@@ -83,7 +83,10 @@ template<typename T> struct IndirectHelper {
   typedef T mutable_return_type;
   static const size_t element_stride = sizeof(T);
   static return_type Read(const uint8_t *p, uoffset_t i) {
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
     return EndianScalar((reinterpret_cast<const T *>(p))[i]);
+#pragma GCC diagnostic pop
   }
 };
 template<typename T> struct IndirectHelper<Offset<T>> {
@@ -92,7 +95,10 @@ template<typename T> struct IndirectHelper<Offset<T>> {
   static const size_t element_stride = sizeof(uoffset_t);
   static return_type Read(const uint8_t *p, uoffset_t i) {
     p += i * sizeof(uoffset_t);
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
     return reinterpret_cast<return_type>(p + ReadScalar<uoffset_t>(p));
+#pragma GCC diagnostic pop
   }
 };
 template<typename T> struct IndirectHelper<const T *> {
@@ -807,12 +813,18 @@ class vector_downward {
   // Specialized version of push() that avoids memcpy call for small data.
   template<typename T> void push_small(const T &little_endian_t) {
     make_space(sizeof(T));
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
     *reinterpret_cast<T *>(cur_) = little_endian_t;
+#pragma GCC diagnostic pop
   }
 
   template<typename T> void scratch_push_small(const T &t) {
     ensure_space(sizeof(T));
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
     *reinterpret_cast<T *>(scratch_) = t;
+#pragma GCC diagnostic pop
     scratch_ += sizeof(T);
   }
 
@@ -1217,7 +1229,10 @@ class FlatBufferBuilder {
     // Write the offsets into the table
     for (auto it = buf_.scratch_end() - num_field_loc * sizeof(FieldLoc);
          it < buf_.scratch_end(); it += sizeof(FieldLoc)) {
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
       auto field_location = reinterpret_cast<FieldLoc *>(it);
+#pragma GCC diagnostic pop
       auto pos = static_cast<voffset_t>(vtableoffsetloc - field_location->off);
       // If this asserts, it means you've set a field twice.
       FLATBUFFERS_ASSERT(
@@ -1225,7 +1240,10 @@ class FlatBufferBuilder {
       WriteScalar<voffset_t>(buf_.data() + field_location->id, pos);
     }
     ClearOffsets();
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
     auto vt1 = reinterpret_cast<voffset_t *>(buf_.data());
+#pragma GCC diagnostic pop
     auto vt1_size = ReadScalar<voffset_t>(vt1);
     auto vt_use = GetSize();
     // See if we already have generated a vtable with this exact same
@@ -1233,8 +1251,11 @@ class FlatBufferBuilder {
     if (dedup_vtables_) {
       for (auto it = buf_.scratch_data(); it < buf_.scratch_end();
            it += sizeof(uoffset_t)) {
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
         auto vt_offset_ptr = reinterpret_cast<uoffset_t *>(it);
         auto vt2 = reinterpret_cast<voffset_t *>(buf_.data_at(*vt_offset_ptr));
+#pragma GCC diagnostic pop
         auto vt2_size = *vt2;
         if (vt1_size != vt2_size || 0 != memcmp(vt2, vt1, vt1_size)) continue;
         vt_use = *vt_offset_ptr;
@@ -1889,8 +1910,11 @@ protected:
   struct StringOffsetCompare {
     StringOffsetCompare(const vector_downward &buf) : buf_(&buf) {}
     bool operator()(const Offset<String> &a, const Offset<String> &b) const {
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
       auto stra = reinterpret_cast<const String *>(buf_->data_at(a.o));
       auto strb = reinterpret_cast<const String *>(buf_->data_at(b.o));
+#pragma GCC diagnostic pop
       return StringLessThan(stra->data(), stra->size(),
                             strb->data(), strb->size());
     }
@@ -2272,8 +2296,11 @@ class Table {
   template<typename P> P GetPointer(voffset_t field) {
     auto field_offset = GetOptionalFieldOffset(field);
     auto p = data_ + field_offset;
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
     return field_offset ? reinterpret_cast<P>(p + ReadScalar<uoffset_t>(p))
                         : nullptr;
+#pragma GCC diagnostic pop
   }
   template<typename P> P GetPointer(voffset_t field) const {
     return const_cast<Table *>(this)->GetPointer<P>(field);
@@ -2282,7 +2309,10 @@ class Table {
   template<typename P> P GetStruct(voffset_t field) const {
     auto field_offset = GetOptionalFieldOffset(field);
     auto p = const_cast<uint8_t *>(data_ + field_offset);
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
     return field_offset ? reinterpret_cast<P>(p) : nullptr;
+#pragma GCC diagnostic pop
   }
 
   template<typename T> bool SetField(voffset_t field, T val, T def) {
-- 
2.33.1