diff --git a/indra/llcommon/llapr.cpp b/indra/llcommon/llapr.cpp
index db06b6952189c0063a1601ae50d38a26878c18bd..e2184eaec526bb30d16df1bf634d20693ccaa777 100644
--- a/indra/llcommon/llapr.cpp
+++ b/indra/llcommon/llapr.cpp
@@ -332,7 +332,7 @@ apr_status_t LLAPRFile::close()
 	return ret ;
 }
 
-apr_status_t LLAPRFile::open(const std::string& filename, apr_int32_t flags, LLVolatileAPRPool* pool, apr_off_t* sizep)
+apr_status_t LLAPRFile::open(const std::string& filename, apr_int32_t flags, LLVolatileAPRPool* pool, S32* sizep)
 {
 	apr_status_t s ;
 
@@ -355,12 +355,12 @@ apr_status_t LLAPRFile::open(const std::string& filename, apr_int32_t flags, LLV
 	}
 	else if (sizep)
 	{
-		apr_off_t file_size = 0;
+		S32 file_size = 0;
 		apr_off_t offset = 0;
 		if (apr_file_seek(mFile, APR_END, &offset) == APR_SUCCESS)
 		{
-			llassert_always(offset <= std::numeric_limits<apr_off_t>::max());
-			file_size = (apr_off_t)offset;
+			llassert_always(offset <= 0x7fffffff);
+			file_size = (S32)offset;
 			offset = 0;
 			apr_file_seek(mFile, APR_SET, &offset);
 		}
@@ -398,7 +398,7 @@ apr_status_t LLAPRFile::open(const std::string& filename, apr_int32_t flags, BOO
 }
 
 // File I/O
-apr_size_t LLAPRFile::read(void *buf, apr_size_t nbytes)
+S32 LLAPRFile::read(void *buf, S32 nbytes)
 {
 	if(!mFile) 
 	{
@@ -415,12 +415,12 @@ apr_size_t LLAPRFile::read(void *buf, apr_size_t nbytes)
 	}
 	else
 	{
-		llassert_always(sz <= std::numeric_limits<apr_size_t>::max());
-		return (apr_size_t)sz;
+		llassert_always(sz <= 0x7fffffff);
+		return (S32)sz;
 	}
 }
 
-apr_size_t LLAPRFile::write(const void *buf, apr_size_t nbytes)
+S32 LLAPRFile::write(const void *buf, S32 nbytes)
 {
 	if(!mFile) 
 	{
@@ -437,12 +437,12 @@ apr_size_t LLAPRFile::write(const void *buf, apr_size_t nbytes)
 	}
 	else
 	{
-		llassert_always(sz <= std::numeric_limits<apr_size_t>::max());
-		return (apr_size_t)sz;
+		llassert_always(sz <= 0x7fffffff);
+		return (S32)sz;
 	}
 }
 
-apr_off_t LLAPRFile::seek(apr_seek_where_t where, apr_off_t offset)
+S32 LLAPRFile::seek(apr_seek_where_t where, S32 offset)
 {
 	return LLAPRFile::seek(mFile, where, offset) ;
 }
@@ -486,7 +486,7 @@ apr_file_t* LLAPRFile::open(const std::string& filename, apr_pool_t* apr_pool, a
 }
 
 //static
-apr_off_t LLAPRFile::seek(apr_file_t* file_handle, apr_seek_where_t where, apr_off_t offset)
+S32 LLAPRFile::seek(apr_file_t* file_handle, apr_seek_where_t where, S32 offset)
 {
 	if(!file_handle)
 	{
@@ -512,13 +512,13 @@ apr_off_t LLAPRFile::seek(apr_file_t* file_handle, apr_seek_where_t where, apr_o
 	}
 	else
 	{
-		llassert_always(apr_offset <= std::numeric_limits<apr_off_t>::max());
-		return apr_offset;
+		llassert_always(apr_offset <= 0x7fffffff);
+		return (S32)apr_offset;
 	}
 }
 
 //static
-apr_size_t LLAPRFile::readEx(const std::string& filename, void *buf, apr_off_t offset, apr_size_t nbytes, LLVolatileAPRPool* pool)
+S32 LLAPRFile::readEx(const std::string& filename, void *buf, S32 offset, S32 nbytes, LLVolatileAPRPool* pool)
 {
 	//*****************************************
 	LLAPRFilePoolScope scope(pool);
@@ -551,18 +551,18 @@ apr_size_t LLAPRFile::readEx(const std::string& filename, void *buf, apr_off_t o
 		}
 		else
 		{
-			llassert_always(bytes_read <= std::numeric_limits<apr_size_t>::max());
+			llassert_always(bytes_read <= 0x7fffffff);		
 		}
 	}
 	
 	//*****************************************
 	close(file_handle) ; 
 	//*****************************************
-	return bytes_read;
+	return (S32)bytes_read;
 }
 
 //static
-apr_size_t LLAPRFile::writeEx(const std::string& filename, void *buf, apr_off_t offset, apr_size_t nbytes, LLVolatileAPRPool* pool)
+S32 LLAPRFile::writeEx(const std::string& filename, void *buf, S32 offset, S32 nbytes, LLVolatileAPRPool* pool)
 {
 	apr_int32_t flags = APR_CREATE|APR_WRITE|APR_BINARY;
 	if (offset < 0)
@@ -602,7 +602,7 @@ apr_size_t LLAPRFile::writeEx(const std::string& filename, void *buf, apr_off_t
 		}
 		else
 		{
-			llassert_always(bytes_written <= std::numeric_limits<apr_size_t>::max());
+			llassert_always(bytes_written <= 0x7fffffff);
 		}
 	}
 
@@ -610,7 +610,7 @@ apr_size_t LLAPRFile::writeEx(const std::string& filename, void *buf, apr_off_t
 	LLAPRFile::close(file_handle);
 	//*****************************************
 
-	return (apr_size_t)bytes_written;
+	return (S32)bytes_written;
 }
 
 //static
@@ -668,7 +668,7 @@ bool LLAPRFile::isExist(const std::string& filename, LLVolatileAPRPool* pool, ap
 }
 
 //static
-apr_off_t LLAPRFile::size(const std::string& filename, LLVolatileAPRPool* pool)
+S32 LLAPRFile::size(const std::string& filename, LLVolatileAPRPool* pool)
 {
 	apr_file_t* apr_file;
 	apr_finfo_t info;
@@ -683,13 +683,13 @@ apr_off_t LLAPRFile::size(const std::string& filename, LLVolatileAPRPool* pool)
 	}
 	else
 	{
-		s = apr_file_info_get(&info, APR_FINFO_SIZE, apr_file);		
+		apr_status_t s = apr_file_info_get(&info, APR_FINFO_SIZE, apr_file);		
 
 		apr_file_close(apr_file) ;
 		
 		if (s == APR_SUCCESS)
 		{
-			return (apr_off_t)info.size;
+			return (S32)info.size;
 		}
 		else
 		{
diff --git a/indra/llcommon/llapr.h b/indra/llcommon/llapr.h
index 64425fae23047a2bd53a2db70027123d62045191..24374dc77dd4da494725714ecc10399131d7b155 100644
--- a/indra/llcommon/llapr.h
+++ b/indra/llcommon/llapr.h
@@ -162,17 +162,17 @@ class LL_COMMON_API LLAPRFile
 	LLAPRFile(const LLAPRFile&) = delete;
 	LLAPRFile& operator=(const LLAPRFile&) = delete;
 	
-	apr_status_t open(const std::string& filename, apr_int32_t flags, LLVolatileAPRPool* pool = nullptr, apr_off_t* sizep = nullptr);
+	apr_status_t open(const std::string& filename, apr_int32_t flags, LLVolatileAPRPool* pool = NULL, S32* sizep = NULL);
 	apr_status_t open(const std::string& filename, apr_int32_t flags, BOOL use_global_pool); //use gAPRPoolp.
 	apr_status_t close() ;
 
 	// Returns actual offset, -1 if seek fails
-	apr_off_t seek(apr_seek_where_t where, apr_off_t offset);
+	S32 seek(apr_seek_where_t where, S32 offset);
 	apr_status_t eof() { return apr_file_eof(mFile);}
 
 	// Returns bytes read/written, 0 if read/write fails:
-	apr_size_t read(void* buf, apr_size_t nbytes);
-	apr_size_t write(const void* buf, apr_size_t nbytes);
+	S32 read(void* buf, S32 nbytes);
+	S32 write(const void* buf, S32 nbytes);
 	
 	apr_file_t* getFileHandle() {return mFile;}	
 	
@@ -186,19 +186,19 @@ class LL_COMMON_API LLAPRFile
 private:
 	static apr_file_t* open(const std::string& filename, apr_pool_t* apr_pool, apr_int32_t flags);
 	static apr_status_t close(apr_file_t* file) ;
-	static apr_off_t seek(apr_file_t* file, apr_seek_where_t where, apr_off_t offset);
+	static S32 seek(apr_file_t* file, apr_seek_where_t where, S32 offset);
 public:
 	// returns false if failure:
-	static bool remove(const std::string& filename, LLVolatileAPRPool* pool = nullptr);
-	static bool rename(const std::string& filename, const std::string& newname, LLVolatileAPRPool* pool = nullptr);
-	static bool isExist(const std::string& filename, LLVolatileAPRPool* pool = nullptr, apr_int32_t flags = APR_READ);
-	static apr_off_t size(const std::string& filename, LLVolatileAPRPool* pool = nullptr);
-	static bool makeDir(const std::string& dirname, LLVolatileAPRPool* pool = nullptr);
-	static bool removeDir(const std::string& dirname, LLVolatileAPRPool* pool = nullptr);
+	static bool remove(const std::string& filename, LLVolatileAPRPool* pool = NULL);
+	static bool rename(const std::string& filename, const std::string& newname, LLVolatileAPRPool* pool = NULL);
+	static bool isExist(const std::string& filename, LLVolatileAPRPool* pool = NULL, apr_int32_t flags = APR_READ);
+	static S32 size(const std::string& filename, LLVolatileAPRPool* pool = NULL);
+	static bool makeDir(const std::string& dirname, LLVolatileAPRPool* pool = NULL);
+	static bool removeDir(const std::string& dirname, LLVolatileAPRPool* pool = NULL);
 
 	// Returns bytes read/written, 0 if read/write fails:
-	static apr_size_t readEx(const std::string& filename, void *buf, apr_off_t offset, apr_size_t nbytes, LLVolatileAPRPool* pool = nullptr);
-	static apr_size_t writeEx(const std::string& filename, void *buf, apr_off_t offset, apr_size_t nbytes, LLVolatileAPRPool* pool = nullptr); // offset<0 means append
+	static S32 readEx(const std::string& filename, void *buf, S32 offset, S32 nbytes, LLVolatileAPRPool* pool = NULL);	
+	static S32 writeEx(const std::string& filename, void *buf, S32 offset, S32 nbytes, LLVolatileAPRPool* pool = NULL); // offset<0 means append
 //*******************************************************************************************************************************
 };
 
diff --git a/indra/llimage/llimage.cpp b/indra/llimage/llimage.cpp
index 603390a22d1d29d7528400d3eba32075c351d10f..3776673071cccb7d1a8527135a0c16f5ed3e72fe 100644
--- a/indra/llimage/llimage.cpp
+++ b/indra/llimage/llimage.cpp
@@ -2183,7 +2183,7 @@ bool LLImageFormatted::load(const std::string &filename, int load_size)
 {
 	resetLastError();
 
-	apr_off_t file_size = 0;
+	S32 file_size = 0;
 	LLAPRFile infile ;
 	infile.open(filename, LL_APR_RB, NULL, &file_size);
 	apr_file_t* apr_file = infile.getFileHandle();
diff --git a/indra/llimage/llimagedimensionsinfo.cpp b/indra/llimage/llimagedimensionsinfo.cpp
index ab190c18b3e6f63ce2bd807d4430de07d52e0cd7..06042e183f0d3454da06db1ca546b7557b791993 100644
--- a/indra/llimage/llimagedimensionsinfo.cpp
+++ b/indra/llimage/llimagedimensionsinfo.cpp
@@ -41,7 +41,7 @@ bool LLImageDimensionsInfo::load(const std::string& src_filename,U32 codec)
 
 	mSrcFilename = src_filename;
 
-	apr_off_t file_size = 0;
+	S32 file_size = 0;
 	apr_status_t s = mInfile.open(src_filename, LL_APR_RB, NULL, &file_size);
 
 	if (s != APR_SUCCESS)
diff --git a/indra/llimage/llimagej2c.cpp b/indra/llimage/llimagej2c.cpp
index 9fcf053730c5551d9d7517a6a16b7eb31c6c3c8d..625f275a06f21e4c74fb384de3edc369dcbbb9d4 100644
--- a/indra/llimage/llimagej2c.cpp
+++ b/indra/llimage/llimagej2c.cpp
@@ -347,7 +347,7 @@ bool LLImageJ2C::loadAndValidate(const std::string &filename)
 	
 	resetLastError();
 
-	apr_off_t file_size = 0;
+	S32 file_size = 0;
 	LLAPRFile infile ;
 	infile.open(filename, LL_APR_RB, NULL, &file_size);
 	apr_file_t* apr_file = infile.getFileHandle() ;
diff --git a/indra/newview/llfloaterbvhpreview.cpp b/indra/newview/llfloaterbvhpreview.cpp
index 233e8232ccf37c544bbe842becc5c6506242db58..fd91f2c62679a3fa312c02df8d5df395f6af1348 100644
--- a/indra/newview/llfloaterbvhpreview.cpp
+++ b/indra/newview/llfloaterbvhpreview.cpp
@@ -195,7 +195,7 @@ BOOL LLFloaterBvhPreview::postBuild()
 		// loading a bvh file
 
 		// now load bvh file
-		apr_off_t file_size;
+		S32 file_size;
 		
 		LLAPRFile infile ;
 		infile.open(mFilenameAndPath, LL_APR_RB, NULL, &file_size);
diff --git a/indra/newview/llviewerassetupload.cpp b/indra/newview/llviewerassetupload.cpp
index b5658bbc5ee7d46a568d04cd6475bfc2bf49e713..5d8c447ee4ac4c3a0f37b62e7cacda3670fd3d41 100644
--- a/indra/newview/llviewerassetupload.cpp
+++ b/indra/newview/llviewerassetupload.cpp
@@ -455,7 +455,7 @@ LLSD LLNewFileResourceUploadInfo::exportTempFile()
     else if (exten == "bvh")
     {
         assetType = LLAssetType::AT_ANIMATION;
-        apr_off_t file_size;
+        S32 file_size;
         LLAPRFile infile;
         infile.open(filename, LL_APR_RB, nullptr, &file_size);
         if (!infile.getFileHandle())
@@ -566,7 +566,7 @@ LLSD LLNewFileResourceUploadInfo::exportTempFile()
     setAssetType(assetType);
 
     // copy this file into the cache for upload
-    apr_off_t file_size;
+    S32 file_size;
     LLAPRFile infile;
     infile.open(filename, LL_APR_RB, NULL, &file_size);
     if (infile.getFileHandle())