fix: give each SORTING struct its own OldPosOut, OldPosIn

check/fixes.frm

@@ -4656,6 +4656,131 @@ Symbol x;
 .end
 assert succeeded?
 *--#] PullReq691 :
+*--#[ PullReq843_1 :
+#-
+
+#: TermsInSmall 16
+#: LargePatches 10
+#: FilePatches 16
+
+#: SubTermsInSmall 16
+#: SubLargePatches 10
+#: SubFilePatches 10
+
+Off statistics;
+Off threadstats;
+
+CFunction f,sum;
+Symbol i,j,x;
+
+#define N "{2*1776+1}"
+#define BLOWUP "{160+1}"
+
+* Generate enough terms to cause a stage sort:
+Local test = {`N'*(`N'+1)/2}
+	#do i = 1,`N'
+		- f(x^`i')
+	#enddo
+	;
+.sort
+
+* Generate enough terms in a sub-buffer sort to create a sort file:
+Argument f;
+	Identify x^i?pos_ = sum_(j,1,`BLOWUP',x^i*i/`BLOWUP');
+EndArgument;
+
+* Cancel everything:
+Identify f(x?) = x;
+Identify x^i? = 1;
+Print;
+.end
+assert succeeded?
+assert result("test") =~ expr("0")
+*--#] PullReq843_1 :
+*--#[ PullReq843_2 :
+#-
+
+#: TermsInSmall 16
+#: LargePatches 10
+#: FilePatches 16
+
+#: SubTermsInSmall 16
+#: SubLargePatches 10
+#: SubFilePatches 10
+
+Off statistics;
+Off threadstats;
+
+CFunction f,sum;
+Symbol i,j,x;
+
+#define N "{2*1776+1}"
+#define BLOWUP "{160+1}"
+
+* Generate enough terms to cause a stage sort:
+Local test = {`N'*(`N'+1)/2}
+	#do i = 1,`N'
+		- x^`i'
+	#enddo
+	;
+.sort
+
+* Generate enough terms in a sub-buffer sort to create a sort file:
+Term;
+	Identify x^i?pos_ = sum_(j,1,`BLOWUP',x^i*i/`BLOWUP');
+EndTerm;
+
+* Cancel everything:
+Identify x^i? = 1;
+Print;
+.end
+assert succeeded?
+assert result("test") =~ expr("0")
+*--#] PullReq843_2 :
+*--#[ PullReq843_3 :
+#-
+
+#: TermsInSmall 16
+#: LargePatches 10
+#: FilePatches 16
+
+#: SubTermsInSmall 16
+#: SubLargePatches 10
+#: SubFilePatches 10
+
+Off statistics;
+Off threadstats;
+
+CFunction f,sum;
+Symbol i,j,x;
+
+#define N "{2*1776+1}"
+#define BLOWUP "{160+1}"
+
+* Generate enough terms to cause a stage sort:
+Local test = {`N'*(`N'+1)/2}
+	#do i = 1,`N'
+		- f(x^`i')
+	#enddo
+	;
+.sort
+
+#$dol = 1;
+* Generate enough terms in a sub-buffer sort to create a sort file:
+Identify f(x?$dol) = 1;
+Inside $dol;
+	Identify x^i?pos_ = sum_(j,1,`BLOWUP',x^i*i/`BLOWUP');
+EndInside;
+Multiply $dol;
+
+* Cancel everything:
+Identify x^i? = 1;
+Print;
+ModuleOption local $dol;
+.end
+assert succeeded?
+assert result("test") =~ expr("0")
+*--#] PullReq843_3 :
 *--#[ Issue808 :
 #do i=0,9
 Global E`i' = `i';

sources/sort.c

@@ -407,12 +407,7 @@ int NewSort(PHEAD0)
 	PUTZERO(S->file.POposition);
 	S->stage4 = 0;
 	if ( AR.sLevel > AN.MaxFunSorts ) AN.MaxFunSorts = AR.sLevel;
-/*
-	The next variable is for the staged sort only.
-	It should be treated differently
 
-	PUTZERO(AN.OldPosOut);
-*/
 	// Zero the SortVerbose counters:
 	S->verbComparisons = 0;
 	S->verbSBsortTerms = 0;
@@ -3493,7 +3488,7 @@ int MergePatches(WORD par)
 		fout = &(S->file);
 		if ( fout->handle < 0 ) {
 FileMake:
-			PUTZERO(AN.OldPosOut);
+			PUTZERO(S->OldPosOut);
 			if ( ( fhandle = CreateFile(fout->name) ) < 0 ) {
 				MLOCK(ErrorMessageLock);
 				MesPrint("Cannot create file %s",fout->name);
@@ -3552,7 +3547,7 @@ int MergePatches(WORD par)
 		S->fPatches = S->inPatches;
 		S->inPatches = S->iPatches;
 		(S->inNum) = S->fPatchN;
-		AN.OldPosIn = AN.OldPosOut;
+		S->OldPosIn = S->OldPosOut;
 #ifdef WITHZLIB
 		m1 = S->fpincompressed;
 		S->fpincompressed = S->fpcompressed;
@@ -4121,17 +4116,17 @@ int MergePatches(WORD par)
 */
 		(S->fPatchN)++;
 		S->fPatches[S->fPatchN] = position;
-		if ( ISNOTZEROPOS(AN.OldPosIn) ) {		/* We are not done */
+		if ( ISNOTZEROPOS(S->OldPosIn) ) {		/* We are not done */
 
-			SeekFile(fin->handle,&(AN.OldPosIn),SEEK_SET);
+			SeekFile(fin->handle,&(S->OldPosIn),SEEK_SET);
 /*
 			We don't need extra provisions for the zlib compression here.
 			If part of an expression has been sorted, the whole has been so.
 			This means that S->fpincompressed[] will remain the same
 */
 			if ( (ULONG)ReadFile(fin->handle,(UBYTE *)(&(S->inNum)),(LONG)sizeof(WORD)) !=
 				sizeof(WORD)
-			  || (ULONG)ReadFile(fin->handle,(UBYTE *)(&AN.OldPosIn),(LONG)sizeof(POSITION)) !=
+			  || (ULONG)ReadFile(fin->handle,(UBYTE *)(&(S->OldPosIn)),(LONG)sizeof(POSITION)) !=
 				sizeof(POSITION)
 			  || (ULONG)ReadFile(fin->handle,(UBYTE *)S->iPatches,(LONG)((S->inNum)+1)
 					*sizeof(POSITION)) != ((S->inNum)+1)*sizeof(POSITION) ) {
@@ -4408,7 +4403,7 @@ void StageSort(FILEHANDLE *fout)
 */
 		if ( (ULONG)WriteFile(fout->handle,(UBYTE *)(&(S->fPatchN)),(LONG)sizeof(WORD)) !=
 			sizeof(WORD)
-		  || (ULONG)WriteFile(fout->handle,(UBYTE *)(&(AN.OldPosOut)),(LONG)sizeof(POSITION)) !=
+		  || (ULONG)WriteFile(fout->handle,(UBYTE *)(&(S->OldPosOut)),(LONG)sizeof(POSITION)) !=
 			sizeof(POSITION)
 		  || (ULONG)WriteFile(fout->handle,(UBYTE *)(S->fPatches),(LONG)(S->fPatchN+1)
 					*sizeof(POSITION)) != (S->fPatchN+1)*sizeof(POSITION) ) {
@@ -4417,7 +4412,7 @@ void StageSort(FILEHANDLE *fout)
 			MUNLOCK(ErrorMessageLock);
 			Terminate(-1);
 		}
-		AN.OldPosOut = position;
+		S->OldPosOut = position;
 		fout->filesize = position;
 		ADDPOS(fout->filesize,(S->fPatchN+2)*sizeof(POSITION) + sizeof(WORD));
 		fout->POposition = fout->filesize;

sources/structs.h

@@ -1114,6 +1114,8 @@ typedef struct PaRtI {
 typedef struct sOrT {
     FILEHANDLE file;            /* The own sort file */
     POSITION SizeInFile[3];     /* Sizes in the various files */
+    POSITION OldPosIn;          /* Sort file fill positions */
+    POSITION OldPosOut;
     WORD *lBuffer;              /* The large buffer */
     WORD *lTop;                 /* End of the large buffer */
     WORD *lFill;                /* The filling point of the large buffer */
@@ -2198,8 +2200,6 @@ struct T_const {
  */
 
 struct N_const {
-    POSITION OldPosIn;             /* (R) Used in sort. */
-    POSITION OldPosOut;            /* (R) Used in sort */
 	POSITION theposition;          /* () Used in index.c */
     WORD    *EndNest;              /* (R) Nesting of function levels etc. */
     WORD    *Frozen;               /* (R) Bracket info */