diff --git a/src/aig/gia/giaSimBase.c b/src/aig/gia/giaSimBase.c
index 960d2cda9..43bb24e2d 100644
--- a/src/aig/gia/giaSimBase.c
+++ b/src/aig/gia/giaSimBase.c
@@ -3439,7 +3439,7 @@ int Gia_ManRelCheck( Gia_Man_t * p, Vec_Int_t * vIns, Vec_Int_t * vDivs, Vec_Int
 void Gia_ManRelCompute( Gia_Man_t * p, Vec_Int_t * vIns, Vec_Int_t * vDivs, Vec_Int_t * vOuts, Vec_Wrd_t ** pvSimsIn, Vec_Wrd_t ** pvSimsOut )
 {
     Vec_Wrd_t * vSims, * vRel; 
-    Vec_Wrd_t * vSimsDiv = NULL, * vSimsOut = NULL;
+    //Vec_Wrd_t * vSimsDiv = NULL, * vSimsOut = NULL;
 
     Vec_WrdFreeP( &p->vSimsPi );
     p->vSimsPi = Vec_WrdStartTruthTables( Gia_ManCiNum(p) );
diff --git a/src/aig/saig/saigIoa.c b/src/aig/saig/saigIoa.c
index 35d7b7b27..610dd1f90 100644
--- a/src/aig/saig/saigIoa.c
+++ b/src/aig/saig/saigIoa.c
@@ -45,17 +45,17 @@ ABC_NAMESPACE_IMPL_START
 ***********************************************************************/
 char * Saig_ObjName( Aig_Man_t * p, Aig_Obj_t * pObj )
 {
-    static char Buffer[16];
+    static char Buffer[100];
     if ( Aig_ObjIsNode(pObj) || Aig_ObjIsConst1(pObj) )
-        sprintf( Buffer, "n%0*d", Abc_Base10Log(Aig_ManObjNumMax(p)), Aig_ObjId(pObj) );
+        sprintf( Buffer, "n%0*d", (unsigned char)Abc_Base10Log(Aig_ManObjNumMax(p)), Aig_ObjId(pObj) );
     else if ( Saig_ObjIsPi(p, pObj) )
-        sprintf( Buffer, "pi%0*d", Abc_Base10Log(Saig_ManPiNum(p)), Aig_ObjCioId(pObj) );
+        sprintf( Buffer, "pi%0*d", (unsigned char)Abc_Base10Log(Saig_ManPiNum(p)), Aig_ObjCioId(pObj) );
     else if ( Saig_ObjIsPo(p, pObj) )
-        sprintf( Buffer, "po%0*d", Abc_Base10Log(Saig_ManPoNum(p)), Aig_ObjCioId(pObj) );
+        sprintf( Buffer, "po%0*d", (unsigned char)Abc_Base10Log(Saig_ManPoNum(p)), Aig_ObjCioId(pObj) );
     else if ( Saig_ObjIsLo(p, pObj) )
-        sprintf( Buffer, "lo%0*d", Abc_Base10Log(Saig_ManRegNum(p)), Aig_ObjCioId(pObj) - Saig_ManPiNum(p) );
+        sprintf( Buffer, "lo%0*d", (unsigned char)Abc_Base10Log(Saig_ManRegNum(p)), Aig_ObjCioId(pObj) - Saig_ManPiNum(p) );
     else if ( Saig_ObjIsLi(p, pObj) )
-        sprintf( Buffer, "li%0*d", Abc_Base10Log(Saig_ManRegNum(p)), Aig_ObjCioId(pObj) - Saig_ManPoNum(p) );
+        sprintf( Buffer, "li%0*d", (unsigned char)Abc_Base10Log(Saig_ManRegNum(p)), Aig_ObjCioId(pObj) - Saig_ManPoNum(p) );
     else 
         assert( 0 );
     return Buffer;
diff --git a/src/base/abci/abc.c b/src/base/abci/abc.c
index 8a97561ee..19b7237b1 100644
--- a/src/base/abci/abc.c
+++ b/src/base/abci/abc.c
@@ -30990,7 +30990,7 @@ int Abc_CommandAbc9Put( Abc_Frame_t * pAbc, int argc, char ** argv )
     // transfer PO names to pNtk
     if ( pAbc->pGia->vNamesOut )
     {
-        char pSuffix[100];
+        char pSuffix[1000];
         Abc_Obj_t * pObj; int i;
         unsigned char nDigits = (unsigned char)Abc_Base10Log( Abc_NtkLatchNum(pNtk) );
         Abc_NtkForEachCo( pNtk, pObj, i ) {
diff --git a/src/base/io/ioReadPla.c b/src/base/io/ioReadPla.c
index 5277c0451..a8e5fd701 100644
--- a/src/base/io/ioReadPla.c
+++ b/src/base/io/ioReadPla.c
@@ -370,7 +370,7 @@ Abc_Ntk_t * Io_ReadPlaNetwork( Extra_FileReader_t * p, int fZeros, int fBoth, in
     Abc_Ntk_t * pNtk;
     Abc_Obj_t * pTermPi, * pTermPo, * pNode;
     Vec_Str_t ** ppSops = NULL;
-    char Buffer[100];
+    char Buffer[1000];
     int nInputs = -1, nOutputs = -1, nProducts = -1;
     char * pCubeIn, * pCubeOut;
     int i, k, iLine, nCubes;
diff --git a/src/base/wlc/wlcNdr.c b/src/base/wlc/wlcNdr.c
index a5228402e..5419286ff 100644
--- a/src/base/wlc/wlcNdr.c
+++ b/src/base/wlc/wlcNdr.c
@@ -493,7 +493,7 @@ Wlc_Ntk_t * Wlc_NtkFromNdr( void * pData )
     pNtk->pManName = Abc_NamStart( NameIdMax+1, 10 );
     for ( i = 1; i <= NameIdMax; i++ )
     {
-        char pName[100]; sprintf( pName, "s%0*d", nDigits, i );
+        char pName[1000]; sprintf( pName, "s%0*d", nDigits, i );
         NameId = Abc_NamStrFindOrAdd( pNtk->pManName, pName, &fFound );
         assert( !fFound && i == NameId );
     }
diff --git a/src/base/wlc/wlcNtk.c b/src/base/wlc/wlcNtk.c
index 1b04a91f3..5d1097202 100644
--- a/src/base/wlc/wlcNtk.c
+++ b/src/base/wlc/wlcNtk.c
@@ -1292,7 +1292,7 @@ Wlc_Ntk_t * Wlc_NtkDupSingleNodes( Wlc_Ntk_t * p )
 void Wlc_NtkShortNames( Wlc_Ntk_t * p )
 {
     Wlc_Obj_t * pObj;
-    char pBuffer[100];
+    char pBuffer[1000];
     int NameId, fFound, i;
     int nFlops = Wlc_NtkCoNum(p) - Wlc_NtkPoNum(p);
     unsigned char nDigits = (unsigned char)Abc_Base10Log( nFlops );
diff --git a/src/base/wln/wlnNdr.c b/src/base/wln/wlnNdr.c
index 9eaf71ed9..33a530e4e 100644
--- a/src/base/wln/wlnNdr.c
+++ b/src/base/wln/wlnNdr.c
@@ -256,7 +256,7 @@ Wln_Ntk_t * Wln_NtkFromNdr( void * pData, int fDump )
     pNtk->pManName = Abc_NamStart( NameIdMax+1, 10 );
     for ( i = 1; i <= NameIdMax; i++ )
     {
-        char pName[100]; sprintf( pName, "s%0*d", nDigits, i );
+        char pName[1000]; sprintf( pName, "s%0*d", nDigits, i );
         NameId = Abc_NamStrFindOrAdd( pNtk->pManName, pName, &fFound );
         assert( !fFound && i == NameId );
     }
diff --git a/src/bool/kit/kitHop.c b/src/bool/kit/kitHop.c
index 4509dadfe..0e78f62a3 100644
--- a/src/bool/kit/kitHop.c
+++ b/src/bool/kit/kitHop.c
@@ -182,7 +182,7 @@ void Kit_IsopResubInt( Kit_Graph_t * pGraph, Vec_Int_t * vRes )
         Vec_IntPush( vRes, 4 + Abc_Var2Lit(Kit_GraphVarInt(pGraph), Kit_GraphIsComplement(pGraph)) );
     else
     {
-        Kit_Node_t * pNode; int i;
+        Kit_Node_t * pNode = NULL; int i;
         Kit_GraphForEachNode( pGraph, pNode, i )
         {
             Kit_Node_t * pFan0 = Kit_GraphNodeFanin0( pGraph, pNode );
diff --git a/src/map/if/ifDsd.c b/src/map/if/ifDsd.c
index d33c42d64..c25873a9f 100644
--- a/src/map/if/ifDsd.c
+++ b/src/map/if/ifDsd.c
@@ -91,7 +91,7 @@ struct If_DsdMan_t_
     Vec_Mem_t *    vTtMem[IF_MAX_FUNC_LUTSIZE+1];  // truth table memory and hash table
     Vec_Ptr_t *    vTtDecs[IF_MAX_FUNC_LUTSIZE+1]; // truth table decompositions
     Vec_Wec_t *    vIsops[IF_MAX_FUNC_LUTSIZE+1];  // ISOP for each function
-    int *          pSched[IF_MAX_FUNC_LUTSIZE];    // grey code schedules
+    int *          pSched[IF_MAX_FUNC_LUTSIZE+1];  // grey code schedules
     int            nTtBits;        // the number of truth table bits
     int            nConfigWords;   // the number of words for config data per node
     Vec_Wrd_t *    vConfigs;       // permutations
diff --git a/src/map/scl/sclLibUtil.c b/src/map/scl/sclLibUtil.c
index 7197310f9..9624be93e 100644
--- a/src/map/scl/sclLibUtil.c
+++ b/src/map/scl/sclLibUtil.c
@@ -197,11 +197,11 @@ void Abc_SclShortNames( SC_Lib * p )
     char Buffer[10000];
     SC_Cell * pClass, * pCell; SC_Pin * pPin;
     int i, k, n, nClasses = Abc_SclLibClassNum(p);
-    int nDigits = Abc_Base10Log( nClasses );
+    unsigned char nDigits = (unsigned char)Abc_Base10Log( nClasses );
     // itereate through classes
     SC_LibForEachCellClass( p, pClass, i )
     {
-        int nDigits2 = Abc_Base10Log( Abc_SclClassCellNum(pClass) );
+        unsigned char nDigits2 = (unsigned char)Abc_Base10Log( Abc_SclClassCellNum(pClass) );
         SC_RingForEachCell( pClass, pCell, k )
         {
             ABC_FREE( pCell->pName );
@@ -214,13 +214,13 @@ void Abc_SclShortNames( SC_Lib * p )
             SC_CellForEachPinIn( pCell, pPin, n )
             {
                 ABC_FREE( pPin->pName );
-                sprintf( Buffer, "%c", 'a'+n );
+                sprintf( Buffer, "%c", (char)('a'+n) );
                 pPin->pName = Abc_UtilStrsav( Buffer );
             }
             SC_CellForEachPinOut( pCell, pPin, n )
             {
                 ABC_FREE( pPin->pName );
-                sprintf( Buffer, "%c", 'z'-n+pCell->n_inputs );
+                sprintf( Buffer, "%c", (char)('z'-n+pCell->n_inputs) );
                 pPin->pName = Abc_UtilStrsav( Buffer );
             }
         }