diff --git a/lib/common/zstd_internal.h b/lib/common/zstd_internal.h
index 47d7d8ec..8b9b6290 100644
--- a/lib/common/zstd_internal.h
+++ b/lib/common/zstd_internal.h
@@ -210,7 +210,6 @@ typedef struct {
     U32  cachedPrice;
     U32  cachedLitLength;
     const BYTE* cachedLiterals;
-    ZSTD_stats_t stats;
 } seqStore_t;
 
 const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx);
diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index 0a8dde39..a32cb5ad 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -2232,7 +2232,6 @@ static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
     BYTE* const ostart = (BYTE*)dst;
     BYTE* op = ostart;
     U32 const maxDist = 1 << cctx->params.cParams.windowLog;
-    ZSTD_stats_t* stats = &cctx->seqStore.stats;
 
     if (cctx->params.fParams.checksumFlag)
         XXH64_update(&cctx->xxhState, src, srcSize);
diff --git a/lib/compress/zstd_opt.h b/lib/compress/zstd_opt.h
index e3c5cf2e..cb332d94 100644
--- a/lib/compress/zstd_opt.h
+++ b/lib/compress/zstd_opt.h
@@ -500,7 +500,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
                 price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr-1);
            }
 
-           if (cur > last_pos || price <= opt[cur].price) // || ((price == opt[cur].price) && (opt[cur-1].mlen == 1) && (cur != litlen)))
+           if (cur > last_pos || price <= opt[cur].price) 
                 SET_PRICE(cur, 1, 0, litlen, price);
 
            if (cur == last_pos) break;
@@ -532,7 +532,6 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
                             goto _storeSequence;
                        }
 
-                       //best_off = ((i<=1) & (opt[cur].mlen != 1)) ? 1-i : i;
                        best_off = i - (opt[cur].mlen != 1);
 
                        if (opt[cur].mlen == 1) {
@@ -585,7 +584,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
                         SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
 
                     mlen++;
-        }   }   }   // for (cur = 1; cur <= last_pos; cur++)
+        }   }   }
 
         best_mlen = opt[last_pos].mlen;
         best_off = opt[last_pos].off;
@@ -739,7 +738,7 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
 
         best_mlen = (last_pos) ? last_pos : minMatch;
 
-        // set prices using matches at position = 0
+        /* set prices using matches at position = 0 */
         for (u = 0; u < match_num; u++) {
             mlen = (u>0) ? matches[u-1].len+1 : best_mlen;
             best_mlen = matches[u].len;
@@ -752,7 +751,6 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
         }   }
 
         if (last_pos < minMatch) {
-            // ip += ((ip-anchor) >> g_searchStrength) + 1;   /* jump faster over incompressible sections */
             ip++; continue;
         }
 
@@ -771,7 +769,7 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
                 price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr-1);
             }
 
-            if (cur > last_pos || price <= opt[cur].price) // || ((price == opt[cur].price) && (opt[cur-1].mlen == 1) && (cur != litlen)))
+            if (cur > last_pos || price <= opt[cur].price)
                 SET_PRICE(cur, 1, 0, litlen, price);
 
             if (cur == last_pos) break;
diff --git a/lib/decompress/zstd_decompress.c b/lib/decompress/zstd_decompress.c
index 524c2f56..c3d9d608 100644
--- a/lib/decompress/zstd_decompress.c
+++ b/lib/decompress/zstd_decompress.c
@@ -64,7 +64,6 @@
 *  Dependencies
 *********************************************************/
 #include <string.h>      /* memcpy, memmove, memset */
-#include <stdio.h>       /* debug only : printf */
 #include "mem.h"         /* low level memory routines */
 #define XXH_STATIC_LINKING_ONLY   /* XXH64_state_t */
 #include "xxhash.h"      /* XXH64_* */
diff --git a/programs/util.h b/programs/util.h
index 1e4c7977..37ae4cb2 100644
--- a/programs/util.h
+++ b/programs/util.h
@@ -245,7 +245,7 @@ UTIL_STATIC int UTIL_prepareFileList(const char *dirName, char** bufStart, size_
         if (cFile.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
             if (strcmp (cFile.cFileName, "..") == 0 ||
                 strcmp (cFile.cFileName, ".") == 0) continue;
-         //   printf ("[%s]\n", path);
+
             nbFiles += UTIL_prepareFileList(path, bufStart, pos, bufEnd);  /* Recursively call "UTIL_prepareFileList" with the new path. */
             if (*bufStart == NULL) { FindClose(hFile); return 0; }
         }
@@ -261,7 +261,6 @@ UTIL_STATIC int UTIL_prepareFileList(const char *dirName, char** bufStart, size_
                 *pos += pathLength + 1;
                 nbFiles++;
             }
-         //   printf ("%s\\%s nbFiles=%d left=%d\n", dirName, cFile.cFileName, nbFiles, (int)(bufEnd - *bufStart));
         }
     } while (FindNextFile(hFile, &cFile));
 
@@ -297,7 +296,6 @@ UTIL_STATIC int UTIL_prepareFileList(const char *dirName, char** bufStart, size_
             continue;
         }
         if (UTIL_isDirectory(path)) {
-         //   printf ("[%s]\n", path);
             nbFiles += UTIL_prepareFileList(path, bufStart, pos, bufEnd);  /* Recursively call "UTIL_prepareFileList" with the new path. */
             if (*bufStart == NULL) { closedir(dir); return 0; }
         } else {
@@ -312,9 +310,8 @@ UTIL_STATIC int UTIL_prepareFileList(const char *dirName, char** bufStart, size_
                 *pos += pathLength + 1;
                 nbFiles++;
             }
-         //   printf ("%s/%s nbFiles=%d left=%d\n", dirName, entry->d_name, nbFiles, (int)(bufEnd - *bufStart));
         }
-        errno = 0; // clear errno after UTIL_isDirectory, UTIL_prepareFileList
+        errno = 0; /* clear errno after UTIL_isDirectory, UTIL_prepareFileList */
     }
 
     if (errno != 0) {
@@ -335,7 +332,7 @@ UTIL_STATIC int UTIL_prepareFileList(const char *dirName, char** bufStart, size_
     return 0;
 }
 
-#endif // #ifdef _WIN32
+#endif /* #ifdef _WIN32 */
 
 /*
  * UTIL_createFileList - takes a list of files and directories (params: inputNames, inputNamesNb), scans directories,
diff --git a/zlibWrapper/zstd_zlibwrapper.c b/zlibWrapper/zstd_zlibwrapper.c
index e23a235c..0218c6a2 100644
--- a/zlibWrapper/zstd_zlibwrapper.c
+++ b/zlibWrapper/zstd_zlibwrapper.c
@@ -44,7 +44,7 @@
 #define ZWRAP_HEADERSIZE            4
 #define ZWRAP_DEFAULT_CLEVEL        5   /* Z_DEFAULT_COMPRESSION is translated to ZWRAP_DEFAULT_CLEVEL for zstd */
 
-#define LOG_WRAPPER(...)  // printf(__VA_ARGS__)
+#define LOG_WRAPPER(...)  /* printf(__VA_ARGS__) */
 
 
 #define FINISH_WITH_GZ_ERR(msg) { \
@@ -236,8 +236,6 @@ ZEXTERN int ZEXPORT z_deflate OF((z_streamp strm, int flush))
         } else {
             bytesLeft = ZBUFF_compressEnd(zwc->zbc, strm->next_out, &dstCapacity);
             LOG_WRAPPER("ZBUFF_compressEnd dstCapacity=%d bytesLeft=%d\n", (int)dstCapacity, (int)bytesLeft);
-      //      { size_t const errorCode = ZBUFF_compressInit(zwc->zbc, 1);
-      //        if (ZSTD_isError(errorCode)) return Z_MEM_ERROR; }
         }
         if (ZSTD_isError(bytesLeft)) return Z_MEM_ERROR;
         strm->next_out += dstCapacity;
@@ -752,7 +750,6 @@ ZEXTERN int ZEXPORT z_uncompress OF((Bytef *dest,   uLongf *destLen,
                                    const Bytef *source, uLong sourceLen))
 {
     if (sourceLen < 4 || MEM_readLE32(source) != ZSTD_MAGICNUMBER)
-//    if (!g_useZSTD)
         return uncompress(dest, destLen, source, sourceLen);
 
     { size_t dstCapacity = *destLen; 
@@ -856,7 +853,6 @@ ZEXTERN int ZEXPORTVA z_gzprintf OF((gzFile file, const char *format, ...))
         va_end (args);
 
         ret = gzprintf(file, buf);
-      //  printf("gzprintf ret=%d\n", ret);
         return ret;
     }
     FINISH_WITH_GZ_ERR("gzprintf is not supported!");