Add a utility program that looks for assert(), NEVER(), ALWAYS(), and
testcase() macros that have side-effects, and reports errors when they are
found.  Also fix a bug that this utility detected as it was being tested.

FossilOrigin-Name: b0b4624fc5d53bb0cc9fae7dad51984837d946ac
diff --git a/src/btree.c b/src/btree.c
index b99820d..c6f9c34 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -6148,7 +6148,7 @@
   {
     CellInfo info;
     pPage->xParseCell(pPage, pCell, &info);
-    assert( nHeader=(int)(info.pPayload - pCell) );
+    assert( nHeader==(int)(info.pPayload - pCell) );
     assert( info.nKey==nKey );
     assert( *pnSize == info.nSize );
     assert( spaceLeft == info.nLocal );
@@ -7807,8 +7807,8 @@
   u8 aBalanceQuickSpace[13];
   u8 *pFree = 0;
 
-  TESTONLY( int balance_quick_called = 0 );
-  TESTONLY( int balance_deeper_called = 0 );
+  VVA_ONLY( int balance_quick_called = 0 );
+  VVA_ONLY( int balance_deeper_called = 0 );
 
   do {
     int iPage = pCur->iPage;
@@ -7821,7 +7821,8 @@
         ** and copy the current contents of the root-page to it. The
         ** next iteration of the do-loop will balance the child page.
         */ 
-        assert( (balance_deeper_called++)==0 );
+        assert( balance_deeper_called==0 );
+        VVA_ONLY( balance_deeper_called++ );
         rc = balance_deeper(pPage, &pCur->apPage[1]);
         if( rc==SQLITE_OK ){
           pCur->iPage = 1;
@@ -7860,7 +7861,8 @@
           ** function. If this were not verified, a subtle bug involving reuse
           ** of the aBalanceQuickSpace[] might sneak in.
           */
-          assert( (balance_quick_called++)==0 );
+          assert( balance_quick_called==0 ); 
+          VVA_ONLY( balance_quick_called++ );
           rc = balance_quick(pParent, pPage, aBalanceQuickSpace);
         }else
 #endif
@@ -9327,7 +9329,8 @@
 
   sqlite3BtreeEnter(p);
   assert( p->inTrans>TRANS_NONE && pBt->inTransaction>TRANS_NONE );
-  assert( (nRef = sqlite3PagerRefcount(pBt->pPager))>=0 );
+  VVA_ONLY( nRef = sqlite3PagerRefcount(pBt->pPager) );
+  assert( nRef>=0 );
   sCheck.pBt = pBt;
   sCheck.pPager = pBt->pPager;
   sCheck.nPage = btreePagecount(sCheck.pBt);
diff --git a/src/main.c b/src/main.c
index 588461b..922af13 100644
--- a/src/main.c
+++ b/src/main.c
@@ -3566,7 +3566,7 @@
     */
     case SQLITE_TESTCTRL_ASSERT: {
       volatile int x = 0;
-      assert( (x = va_arg(ap,int))!=0 );
+      assert( /*side-effects-ok*/ (x = va_arg(ap,int))!=0 );
       rc = x;
       break;
     }