additional report on spa loading failed

gistfile1.diff

--- src\sphinx.cpp
+++ src\sphinx.cpp
@@ -680,14 +680,14 @@
 	}
 	if ( bCheckSizeT )
 	{
 		size_t sCheck = (size_t)st.st_size;
 		if ( st.st_size!=SphOffset_t(sCheck) )
 		{
-			sError.SetSprintf ( "failed to load %s: bad size "INT64_FMT" (out of size_t; 4 GB limit on 32-bit machine hit?)",
-				GetFilename(), (int64_t)st.st_size );
+			sError.SetSprintf ( "failed to load %s: bad size "INT64_FMT"("INT64_FMT") (out of size_t; 4 GB limit on 32-bit machine hit?)",
+				GetFilename(), (int64_t)st.st_size, SphOffset_t(sCheck) );
 			return -1;
 		}
 	}
 	return st.st_size;
 }
 
@@ -14853,12 +14853,14 @@
 
 		CSphAutofile tDocinfo ( GetIndexFileName("spa"), SPH_O_READ, m_sLastError );
 		if ( tDocinfo.GetFD()<0 )
 			return false;
 
 		int64_t iDocinfoSize = tDocinfo.GetSize ( iEntrySize, true, m_sLastError ) / sizeof(DWORD);
+		if ( iDocinfoSize<0 )
+			return false;
 
 		int64_t iRealDocinfoSize = m_uMinMaxIndex ? m_uMinMaxIndex : iDocinfoSize;
 
 		// intentionally losing data; we don't support more than 4B documents per instance yet
 		m_uDocinfo = (DWORD)( iRealDocinfoSize / iStride );
 		if ( iRealDocinfoSize!=(int64_t)m_uDocinfo*iStride && !m_bId32to64 )
@@ -14892,13 +14894,14 @@
 
 			m_pDocinfoIndex = m_pDocinfo.GetWritePtr()+iDocinfoSize;
 		} else
 		{
 			if ( iDocinfoSize < iRealDocinfoSize )
 			{
-				m_sLastError.SetSprintf ( "precomputed chunk size check mismatch" );
+				m_sLastError.SetSprintf ( "precomputed chunk size check mismatch (docinfo="INT64_FMT", real="INT64_FMT", rows=%d, min-max="INT64_FMT")",
+					iDocinfoSize, iRealDocinfoSize, m_uDocinfo, m_uMinMaxIndex );
 				return false;
 			}
 
 			m_uDocinfoIndex = (DWORD)( ( ( iDocinfoSize - iRealDocinfoSize ) / (m_bId32to64?iStride2:iStride) / 2 ) - 1 );
 
 			// prealloc docinfo