Swap Boost.Container's small_vector out for LLVM's

This implementation misses a shrink to fit function, but reassigning the
vector with a fresh one should be equivalent.

src/common/serialization/vst3/event-list.h

@@ -16,18 +16,15 @@
 
 #pragma once
 
+#include <llvm/small-vector.h>
 #include <pluginterfaces/vst/ivstevents.h>
-#include <boost/container/small_vector.hpp>
 
 #include "../../bitsery/ext/in-place-variant.h"
+#include "../../bitsery/traits/small-vector.h"
 #include "base.h"
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-// FIXME: When used in a Boost.Containers small vector, GCC somehow complains
-//        that the fields in `YaEvent` may be uninitialized (during the
-//        deserialization). This warning only shows up during a unity build.
-#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
 
 /**
  * A wrapper around `DataEvent` for serialization purposes, as this event
@@ -270,7 +267,7 @@ class YaEventList : public Steinberg::Vst::IEventList {
     }
 
    private:
-    boost::container::small_vector<YaEvent, 64> events_;
+    llvm::SmallVector<YaEvent, 64> events_;
 };
 
 #pragma GCC diagnostic pop

src/common/serialization/vst3/param-value-queue.h

@@ -16,20 +16,14 @@
 
 #pragma once
 
+#include <llvm/small-vector.h>
 #include <pluginterfaces/vst/ivstparameterchanges.h>
-#include <boost/container/small_vector.hpp>
 
 #include "../../bitsery/traits/small-vector.h"
 #include "base.h"
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-// FIXME: When used in a Boost.Containers small vector, GCC somehow complains
-//        that the fields in this class may be uninitialized (during the
-//        deserialization). This warning only shows up during a unity build.
-#if defined(__GNUC__) && !defined(__llvm__)
-#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
-#endif
 
 /**
  * Wraps around `IParamValueQueue` for serializing a queue containing changes to
@@ -102,9 +96,7 @@ class alignas(16) YaParamValueQueue : public Steinberg::Vst::IParamValueQueue {
      *
      * This contains pairs of `(sample_offset, value)`.
      */
-    boost::container::small_vector<std::pair<int32, Steinberg::Vst::ParamValue>,
-                                   16>
-        queue_;
+    llvm::SmallVector<std::pair<int32, Steinberg::Vst::ParamValue>, 16> queue_;
 };
 
 #pragma GCC diagnostic pop

src/common/serialization/vst3/parameter-changes.h

@@ -16,8 +16,8 @@
 
 #pragma once
 
+#include <llvm/small-vector.h>
 #include <pluginterfaces/vst/ivstparameterchanges.h>
-#include <boost/container/small_vector.hpp>
 
 #include "../../bitsery/traits/small-vector.h"
 #include "base.h"
@@ -85,7 +85,7 @@ class YaParameterChanges : public Steinberg::Vst::IParameterChanges {
     /**
      * The parameter value changes queues.
      */
-    boost::container::small_vector<YaParamValueQueue, 16> queues_;
+    llvm::SmallVector<YaParamValueQueue, 16> queues_;
 };
 
 #pragma GCC diagnostic pop

src/common/serialization/vst3/process-data.h

@@ -112,8 +112,8 @@ class YaProcessData {
     struct Response {
         // We store raw pointers instead of references so we can default
         // initialize this object during deserialization
-        boost::container::small_vector_base<Steinberg::Vst::AudioBusBuffers>*
-            outputs = nullptr;
+        llvm::SmallVectorImpl<Steinberg::Vst::AudioBusBuffers>* outputs =
+            nullptr;
         std::optional<YaParameterChanges>* output_parameter_changes = nullptr;
         std::optional<YaEventList>* output_events = nullptr;
 
@@ -206,7 +206,7 @@ class YaProcessData {
      * be set to point to our shared memory surface that holds the actual audio
      * data.
      */
-    boost::container::small_vector<Steinberg::Vst::AudioBusBuffers, 8> inputs_;
+    llvm::SmallVector<Steinberg::Vst::AudioBusBuffers, 8> inputs_;
 
     /**
      * This contains metadata about the output buffers for every bus. During
@@ -214,7 +214,7 @@ class YaProcessData {
      * be set to point to our shared memory surface that holds the actual audio
      * data.
      */
-    boost::container::small_vector<Steinberg::Vst::AudioBusBuffers, 8> outputs_;
+    llvm::SmallVector<Steinberg::Vst::AudioBusBuffers, 8> outputs_;
 
     /**
      * Incoming parameter changes.