From c5cc870ef88c76ff6f234eb542700a54354bd3ae Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 19 Jul 2019 15:00:32 +0000
Subject: [PATCH] Refinement to check-in [348e7f193a963390] that avoids
 unreachable branches.

FossilOrigin-Name: bbfb2908ecd113c88e69a0984cbe2550463cdd3a67648b0e4e3578e80630136e
---
 manifest      | 14 +++++++-------
 manifest.uuid |  2 +-
 src/walker.c  | 21 ++++++++++++++++-----
 3 files changed, 24 insertions(+), 13 deletions(-)

diff --git a/manifest b/manifest
index 78752a8440..1ba5fd894e 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\sproblem\swith\srenaming\sa\stable\swhen\sthe\sschema\scontains\san\sinvocation\sof\sa\swindow\sfunction\sthat\sis\snot\scurrently\sregistered.
-D 2019-07-19T14:32:42.623
+C Refinement\sto\scheck-in\s[348e7f193a963390]\sthat\savoids\sunreachable\sbranches.
+D 2019-07-19T15:00:32.611
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -607,7 +607,7 @@ F src/vtab.c 1fa256c6ddad7a81e2a4dc080d015d4b0a7135767717d311298e47f6fca64bb3
 F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c bbd6838bd79c0a32144d482fb0b6a9d2d1a252fb3b16d5005ec30f2f80413b0d
 F src/wal.h 606292549f5a7be50b6227bd685fa76e3a4affad71bb8ac5ce4cb5c79f6a176a
-F src/walker.c 20a8455cfd5ccd9ebbf9efe434b828b890ae71574a5659a95848d6f55cecd602
+F src/walker.c d5a94907dcac990e31976be9dc769d17f6a806782593d6aec9d760ee01ec22cd
 F src/where.c 2f508c9a6dd2a42ad2b692105e77eb92cdec201d32916962ccdeff71836acb52
 F src/whereInt.h 1b728f71654ebf8421a1715497a587f02d6f538e819af58dc826908f8577e810
 F src/wherecode.c 37a1004237d630d785c47bba2290eac652a7a8b0047518eba3cb7c808b604c4a
@@ -1837,7 +1837,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 348e7f193a963390a0595183d603541f85c5d1a911c98ed2e06599691ffe98f5
-R 2caa2651096f2a30c0266bd0880e783b
-U dan
-Z 31de9586c7ae48f0b0e62ceaa957aebc
+P ff290feb97f689cf6ce4162d6aa36f9f9dcf1bff3096847d53a85f39f728d2de
+R 6535622f80dc0d9ebf53ef790422b635
+U drh
+Z e57ea86f45822a56c5c84129128f3a39
diff --git a/manifest.uuid b/manifest.uuid
index d0a89447e0..de2654ef1f 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-ff290feb97f689cf6ce4162d6aa36f9f9dcf1bff3096847d53a85f39f728d2de
\ No newline at end of file
+bbfb2908ecd113c88e69a0984cbe2550463cdd3a67648b0e4e3578e80630136e
\ No newline at end of file
diff --git a/src/walker.c b/src/walker.c
index e1ceaacfe3..67ecd8a809 100644
--- a/src/walker.c
+++ b/src/walker.c
@@ -25,11 +25,22 @@
 static int walkWindowList(Walker *pWalker, Window *pList){
   Window *pWin;
   for(pWin=pList; pWin; pWin=pWin->pNextWin){
-    if( sqlite3WalkExprList(pWalker, pWin->pOrderBy) ) return WRC_Abort;
-    if( sqlite3WalkExprList(pWalker, pWin->pPartition) ) return WRC_Abort;
-    if( sqlite3WalkExpr(pWalker, pWin->pFilter) ) return WRC_Abort;
-    if( sqlite3WalkExpr(pWalker, pWin->pStart) ) return WRC_Abort;
-    if( sqlite3WalkExpr(pWalker, pWin->pEnd) ) return WRC_Abort;
+    int rc;
+    rc = sqlite3WalkExprList(pWalker, pWin->pOrderBy);
+    if( rc ) return WRC_Abort;
+    rc = sqlite3WalkExprList(pWalker, pWin->pPartition);
+    if( rc ) return WRC_Abort;
+    rc = sqlite3WalkExpr(pWalker, pWin->pFilter);
+    if( rc ) return WRC_Abort;
+
+    /* The next two are purely for calls to sqlite3RenameExprUnmap()
+    ** within sqlite3WindowOffsetExpr().  Because of constraints imposed
+    ** by sqlite3WindowOffsetExpr(), they can never fail.  The results do
+    ** not matter anyhow. */
+    rc = sqlite3WalkExpr(pWalker, pWin->pStart);
+    if( NEVER(rc) ) return WRC_Abort;
+    rc = sqlite3WalkExpr(pWalker, pWin->pEnd);
+    if( NEVER(rc) ) return WRC_Abort;
   }
   return WRC_Continue;
 }