diff --git a/include/JSystem/JAudio2/JAISeMgr.h b/include/JSystem/JAudio2/JAISeMgr.h
index 50f81fb1b4..928d85525b 100644
--- a/include/JSystem/JAudio2/JAISeMgr.h
+++ b/include/JSystem/JAudio2/JAISeMgr.h
@@ -15,7 +15,7 @@ struct JASNonCopyable {
     JASNonCopyable() {}
     ~JASNonCopyable() {}
 
-    /* 0x0 */ int field_0x0;
+    /* 0x0 */ void* field_0x0;
 };  // Size: 0x4
 
 /**
@@ -56,7 +56,7 @@ public:
         mParams.init();
         mMaxActiveSe = 0;
         mMaxInactiveSe = 0;
-        field_0x0 = 0;
+        field_0x0 = NULL;
     }
 
     virtual bool isUsingSeqData(const JAISeqDataRegion& seqDataRegion);
diff --git a/include/JSystem/JHostIO/JORMContext.h b/include/JSystem/JHostIO/JORMContext.h
index 99de2bac17..551c2410f2 100644
--- a/include/JSystem/JHostIO/JORMContext.h
+++ b/include/JSystem/JHostIO/JORMContext.h
@@ -249,7 +249,7 @@ public:
      */
     DEFINE_GEN_SLIDER(u8, 0x100 | jhostio::EKind_8B)
     DEFINE_GEN_SLIDER(s16, jhostio::EKind_16B)
-    DEFINE_GEN_SLIDER(f32, JORPropertyEvent::EKind_FloatValue | jhostio::EKind_32B)
+    DEFINE_GEN_SLIDER(f32, (u32)JORPropertyEvent::EKind_FloatValue | (u32)jhostio::EKind_32B)
     DEFINE_GEN_SLIDER(s32, jhostio::EKind_32B)
 
     DEFINE_GEN_SLIDER_ID(f64, JORPropertyEvent::EKind_ValueID | JORPropertyEvent::EKind_FloatValue)
diff --git a/include/JSystem/JSupport/JSupport.h b/include/JSystem/JSupport/JSupport.h
index 5b6b26a20f..1940e6dff8 100644
--- a/include/JSystem/JSupport/JSupport.h
+++ b/include/JSystem/JSupport/JSupport.h
@@ -24,7 +24,7 @@ T* JSUConvertOffsetToPtr(const void* ptr, u32 offset) {
 T* JSUConvertOffsetToPtr(const void* ptr, const void* offset) {
 #endif
     T* ret;
-    if (offset == NULL) {
+    if (offset == 0) {
         ret = NULL;
     } else {
         ret = (T*)((intptr_t)ptr + (intptr_t)offset);
diff --git a/include/JSystem/JUtility/JUTAssert.h b/include/JSystem/JUtility/JUTAssert.h
index e10171f992..03306a8f8a 100644
--- a/include/JSystem/JUtility/JUTAssert.h
+++ b/include/JSystem/JUtility/JUTAssert.h
@@ -60,13 +60,13 @@ JUTAssertion::showAssert_f(JUTAssertion::getSDevice(), __FILE__, __LINE__, MSG,
     OSPanic(__FILE__, __LINE__, "Halt");
 
 #define JUT_WARN_DEVICE(LINE, DEVICE, ...)                                                                        \
-    JUTAssertion::setWarningMessage_f(DEVICE, __FILE__, __LINE__, __VA_ARGS__);    \
+    JUTAssertion::setWarningMessage_f(DEVICE, const_cast<char*>(__FILE__), __LINE__, __VA_ARGS__);    \
 
 #define JUT_LOG(LINE, ...)                                                                         \
-    JUTAssertion::setLogMessage_f(JUTAssertion::getSDevice(), __FILE__, __LINE__, __VA_ARGS__)
+    JUTAssertion::setLogMessage_f(JUTAssertion::getSDevice(), const_cast<char*>(__FILE__), __LINE__, __VA_ARGS__)
 
 #define JUT_SET_CONFIRM(LINE, COND)                                                                \
-    JUTAssertion::setConfirmMessage(JUTAssertion::getSDevice(), __FILE__, __LINE__, COND, #COND)
+    JUTAssertion::setConfirmMessage(JUTAssertion::getSDevice(), const_cast<char*>(__FILE__), __LINE__, COND, #COND)
 
 #endif
 #define JUT_WARN(LINE, ...)                                                                        \
diff --git a/include/dusk/math.h b/include/dusk/math.h
index 578ff80398..14c50db90a 100644
--- a/include/dusk/math.h
+++ b/include/dusk/math.h
@@ -3,7 +3,9 @@
 
 #include <cmath>
 
+#ifndef M_PI
 #define M_PI 3.14159265358979323846f
+#endif
 #define M_SQRT3 1.73205f
 
 #define DEG_TO_RAD(degrees) (degrees * (M_PI / 180.0f))
diff --git a/include/f_op/f_op_actor.h b/include/f_op/f_op_actor.h
index d743c143f2..6aa5713e1b 100644
--- a/include/f_op/f_op_actor.h
+++ b/include/f_op/f_op_actor.h
@@ -199,7 +199,7 @@ public:
     BOOL chkCondition(u16 condition) { return (mCondition & condition) == condition; }
 
     void suspendProc(void* actor) {
-        if (field_0x10 != NULL) {
+        if (field_0x10 != 0) {
             field_0x14(actor);
         }
     }
diff --git a/include/f_op/f_op_actor_mng.h b/include/f_op/f_op_actor_mng.h
index 83f009a41e..b3a8873bcc 100644
--- a/include/f_op/f_op_actor_mng.h
+++ b/include/f_op/f_op_actor_mng.h
@@ -423,7 +423,14 @@ inline BOOL fopAcM_CULLSIZE_IS_BOX(int i_culltype) {
            i_culltype == fopAc_CULLBOX_CUSTOM_e;
 }
 
-inline const cXyz& fopAcM_getCullSizeSphereCenter(const fopAc_ac_c* i_actor) {
+inline
+#ifdef __MWERKS__
+// In the original code, this constructs a temporary and returns a reference to it
+const cXyz&
+#else
+const Vec&
+#endif
+fopAcM_getCullSizeSphereCenter(const fopAc_ac_c* i_actor) {
     return i_actor->cull.sphere.center;
 }
 
diff --git a/src/JSystem/J2DGraph/J2DMaterialFactory.cpp b/src/JSystem/J2DGraph/J2DMaterialFactory.cpp
index c8c9fc65f7..fdb604f01b 100644
--- a/src/JSystem/J2DGraph/J2DMaterialFactory.cpp
+++ b/src/JSystem/J2DGraph/J2DMaterialFactory.cpp
@@ -248,7 +248,7 @@ u16 J2DMaterialFactory::newTexNo(int param_0, int param_1) const {
     if (iVar2->field_0x38[param_1] != 0xffff) {
         return field_0x28[iVar2->field_0x38[param_1]];
     }
-    return 0x1FFFF;
+    return 0xFFFF;
 }
 
 u16 J2DMaterialFactory::newFontNo(int param_0) const {
@@ -256,7 +256,7 @@ u16 J2DMaterialFactory::newFontNo(int param_0) const {
     if (iVar2->field_0x48 != 0xffff) {
         return field_0x2c[iVar2->field_0x48];
     }
-    return 0x1FFFF;
+    return 0xFFFF;
 }
 
 J2DTevOrder J2DMaterialFactory::newTevOrder(int param_0, int param_1) const {
diff --git a/src/JSystem/JKernel/JKRAramArchive.cpp b/src/JSystem/JKernel/JKRAramArchive.cpp
index f13f7fcbac..5ed1bc181c 100644
--- a/src/JSystem/JKernel/JKRAramArchive.cpp
+++ b/src/JSystem/JKernel/JKRAramArchive.cpp
@@ -208,7 +208,7 @@ void* JKRAramArchive::fetchResource(SDIFileEntry* pEntry, u32* pOutSize) {
             &outBuf);
 
         *pOutSize = size;
-        if (size == NULL) {
+        if (size == 0) {
             return NULL;
         }
 
@@ -243,7 +243,7 @@ void* JKRAramArchive::fetchResource(void* buffer, u32 bufferSize, SDIFileEntry*
     } else {
         if (compression == COMPRESSION_YAZ0) {
             u32 expandSize = this->getExpandSize(pEntry);
-            if (expandSize != NULL) {
+            if (expandSize != 0) {
                 size = expandSize;
             }
         }
diff --git a/src/JSystem/JKernel/JKRAramStream.cpp b/src/JSystem/JKernel/JKRAramStream.cpp
index 94b9ca91fc..76324f6f14 100644
--- a/src/JSystem/JKernel/JKRAramStream.cpp
+++ b/src/JSystem/JKernel/JKRAramStream.cpp
@@ -128,7 +128,7 @@ s32 JKRAramStream::writeToAram(JKRAramStreamCommand* command) {
         }
     }
 
-    OSSendMessage(&command->mMessageQueue, (OSMessage)writtenLength, OS_MESSAGE_NOBLOCK);
+    OSSendMessage(&command->mMessageQueue, (OSMessage)(uintptr_t)writtenLength, OS_MESSAGE_NOBLOCK);
     return writtenLength;
 }
 
diff --git a/src/JSystem/JUtility/JUTGraphFifo.cpp b/src/JSystem/JUtility/JUTGraphFifo.cpp
index 2ec9de1de2..840eca7523 100644
--- a/src/JSystem/JUtility/JUTGraphFifo.cpp
+++ b/src/JSystem/JUtility/JUTGraphFifo.cpp
@@ -18,7 +18,7 @@ JUTGraphFifo::JUTGraphFifo(u32 size) {
         GXInitFifoPtrs(mFifo, mBase, mBase);
     } else {
         mBase = JKRAllocFromSysHeap(mSize + 0xA0, 32);
-        mBase = (void*)ROUND((intptr_t)mBase, 0x20);
+        mBase = (void*)ALIGN_NEXT((intptr_t)mBase, 0x20);
         mFifo = GXInit(mBase, mSize);
         GXSetColorUpdate(GX_ENABLE);
         data_804514B8 = true;