From: drh <>
Date: Tue, 19 Mar 2024 10:46:41 +0000 (+0000)
Subject: Fix a problem involving infinities int the Kahan-Babushka-Neumaier summation algorithm.
X-Git-Tag: version-3.44.3~13
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0febad8fdf5495dc753100269159147def8ee42d;p=thirdparty%2Fsqlite.git

Fix a problem involving infinities int the Kahan-Babushka-Neumaier summation algorithm.

FossilOrigin-Name: 0984e5cd2574780dc1952e3daebafba9ddbb3b4937325117b922fdad0652db57
---

diff --git a/manifest b/manifest
index 9cf2ed0156..e0a7732bed 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Silently\signore\sredundant\sON\sCONFLICT\sclauses\sin\san\sUPSERT.
-D 2024-03-08T14:16:20.687
+C Fix\sa\sproblem\sinvolving\sinfinities\sint\sthe\sKahan-Babushka-Neumaier\ssummation\salgorithm.
+D 2024-03-19T10:46:41.593
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -677,7 +677,7 @@ F src/delete.c cb766727c78e715f9fb7ec8a7d03658ed2a3016343ca687acfcec9083cdca500
 F src/expr.c cacf230b124891ea830d80395ea2119c2d7ee52c134a010f3950de9391ab79d1
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c a47610f0a5c6cb0ad79f8fcef039c01833dec0c751bb695f28dc0ec6a4c3ba00
-F src/func.c 472f6dcfa39cf54f89a6aec76c79c225fb880a6c14469c15d361331662b9bf43
+F src/func.c f8acebf8d6c4f38af99f766754650b26bca1eee058739834899896ce724e43b7
 F src/global.c 29f56a330ed9d1b5cd9b79ac0ca36f97ac3afc730ff8bfa987b0db9e559d684d
 F src/hash.c 9ee4269fb1d6632a6fecfb9479c93a1f29271bddbbaf215dd60420bcb80c7220
 F src/hash.h 3340ab6e1d13e725571d7cee6d3e3135f0779a7d8e76a9ce0a85971fa3953c51
@@ -729,7 +729,7 @@ F src/shell.c.in cbe850737d4166347bfe5fc7d695229379347509bf114cf6abeb1e384f2d7a7
 F src/sqlite.h.in 4f841d3d117b830ee5ee45e8d89ceff1195f3ebb72d041ace8d116ba4c103b35
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 3f046c04ea3595d6bfda99b781926b17e672fd6d27da2ba6d8d8fc39981dcb54
-F src/sqliteInt.h c9be5dccd9bf75f17e278dd328707c8fe59b646995cb0889174bd80e096e0fdb
+F src/sqliteInt.h 99f87f8ac257de1f1e2b6c6d470c016a1c1feb3a13133e36a7d9857c0996b44f
 F src/sqliteLimit.h 33b1c9baba578d34efe7dfdb43193b366111cdf41476b1e82699e14c11ee1fb6
 F src/status.c 160c445d7d28c984a0eae38c144f6419311ed3eace59b44ac6dafc20db4af749
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
@@ -792,7 +792,7 @@ F src/trigger.c 0905b96b04bb6658509f711a8207287f1315cdbc3df1a1b13ba6483c8e341c81
 F src/update.c 6904814dd62a7a93bbb86d9f1419c7f134a9119582645854ab02b36b676d9f92
 F src/upsert.c 2e60567a0e9e8520c18671b30712a88dc73534474304af94f32bb5f3ef65ac65
 F src/utf.c ee39565f0843775cc2c81135751ddd93eceb91a673ea2c57f61c76f288b041a0
-F src/util.c 078f040366d5bd5f47658d045f901c768c1c636c6eaea121f3a1cbd63c3edb5b
+F src/util.c 1e2754e628086dcb93f3f70be7937f0367baa3ad616c4f16f45d61e8ed12c01f
 F src/vacuum.c 604fcdaebe76f3497c855afcbf91b8fa5046b32de3045bab89cc008d68e40104
 F src/vdbe.c b0617c320ae426b0561954dcdb63427fce72d08a4723eb411e3e2b5a7515aa4f
 F src/vdbe.h 88e19a982df9027ec1c177c793d1a5d34dc23d8f06e3b2d997f43688b05ee0eb
@@ -1201,7 +1201,7 @@ F test/fts4umlaut.test fcaca4471de7e78c9d1f7e8976e3e8704d7d8ad979d57a739d00f3f75
 F test/fts4unicode.test 82a9c16b68ba2f358a856226bb2ee02f81583797bc4744061c54401bf1a0f4c9
 F test/fts4upfrom.test f25835162c989dffd5e2ef91ec24c4848cc9973093e2d492d1c7b32afac1b49d
 F test/full.test 6b3c8fb43c6beab6b95438c1675374b95fab245d
-F test/func.test 3a29323b640c0552f6e9f1577407ced3a68e7d8c0bc04b61dd6040fa593a3a02
+F test/func.test 49a39f86fcf374abbfd4f8c428b7420bc3c89095722b511a5503ccc31516d7fe
 F test/func2.test 772d66227e4e6684b86053302e2d74a2500e1e0f
 F test/func3.test 600a632c305a88f3946d38f9a51efe145c989b2e13bd2b2a488db47fe76bab6a
 F test/func4.test 2285fb5792d593fef442358763f0fd9de806eda47dbc7a5934df57ffdc484c31
@@ -2143,9 +2143,10 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 198a1daae01dd9308f91eec1087279481ce0ff632bb3e5ab54cbf3738a903811
-Q +d0ea6b6ba64dba9d68c2b391ccf1171ea96fcdd7409dafdb2b697accb00246b8
-R c2d55bace9f30e2c0a04d1b017926fc2
+P e546d8c68539920ea7b88932e9553d908d6a1956b85e29518ee4f81035987403
+Q +0dddadbd5b217a48bb5c1b0568a03fbafb89dba98c577727bf4f79ff7e0ca849
+Q +45d272ef38d5ee6189f81369aefb8e3ac35868a67687012d93c84f2bbc42520a
+R 89bc076661a68e920df03e2c1ddc99eb
 U drh
-Z d2672131f46ea43c7c9698c6e05c78ec
+Z af93c9415f0626c8dbdfe60bc5719a9d
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 78dd894ad9..4887cf045c 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e546d8c68539920ea7b88932e9553d908d6a1956b85e29518ee4f81035987403
\ No newline at end of file
+0984e5cd2574780dc1952e3daebafba9ddbb3b4937325117b922fdad0652db57
\ No newline at end of file
diff --git a/src/func.c b/src/func.c
index 58ef4fef9c..f8c25a2a73 100644
--- a/src/func.c
+++ b/src/func.c
@@ -1892,7 +1892,7 @@ static void sumFinalize(sqlite3_context *context){
     if( p->approx ){
       if( p->ovrfl ){
         sqlite3_result_error(context,"integer overflow",-1);
-      }else if( !sqlite3IsNaN(p->rErr) ){
+      }else if( !sqlite3IsOverflow(p->rErr) ){
         sqlite3_result_double(context, p->rSum+p->rErr);
       }else{
         sqlite3_result_double(context, p->rSum);
@@ -1909,7 +1909,7 @@ static void avgFinalize(sqlite3_context *context){
     double r;
     if( p->approx ){
       r = p->rSum;
-      if( !sqlite3IsNaN(p->rErr) ) r += p->rErr;
+      if( !sqlite3IsOverflow(p->rErr) ) r += p->rErr;
     }else{
       r = (double)(p->iSum);
     }
@@ -1923,7 +1923,7 @@ static void totalFinalize(sqlite3_context *context){
   if( p ){
     if( p->approx ){
       r = p->rSum;
-      if( !sqlite3IsNaN(p->rErr) ) r += p->rErr;
+      if( !sqlite3IsOverflow(p->rErr) ) r += p->rErr;
     }else{
       r = (double)(p->iSum);
     }
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 6974de3d75..379ae563ce 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -4676,10 +4676,13 @@ void sqlite3MutexWarnOnContention(sqlite3_mutex*);
 # define EXP754 (((u64)0x7ff)<<52)
 # define MAN754 ((((u64)1)<<52)-1)
 # define IsNaN(X) (((X)&EXP754)==EXP754 && ((X)&MAN754)!=0)
+# define IsOvfl(X) (((X)&EXP754)==EXP754)
   int sqlite3IsNaN(double);
+  int sqlite3IsOverflow(double);
 #else
-# define IsNaN(X)         0
-# define sqlite3IsNaN(X)  0
+# define IsNaN(X)             0
+# define sqlite3IsNaN(X)      0
+# define sqlite3IsOVerflow(X) 0
 #endif
 
 /*
diff --git a/src/util.c b/src/util.c
index 207b901bad..7d3a28bae4 100644
--- a/src/util.c
+++ b/src/util.c
@@ -68,6 +68,19 @@ int sqlite3IsNaN(double x){
 }
 #endif /* SQLITE_OMIT_FLOATING_POINT */
 
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** Return true if the floating point value is NaN or +Inf or -Inf.
+*/
+int sqlite3IsOverflow(double x){
+  int rc;   /* The value return */
+  u64 y;
+  memcpy(&y,&x,sizeof(y));
+  rc = IsOvfl(y);
+  return rc;
+}
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+
 /*
 ** Compute a string length that is limited to what can be stored in
 ** lower 30 bits of a 32-bit signed integer.
diff --git a/test/func.test b/test/func.test
index 883950a0c4..ae28db85bf 100644
--- a/test/func.test
+++ b/test/func.test
@@ -1553,4 +1553,25 @@ do_execsql_test func-38.100 {
   WITH t1(x) AS (VALUES(-9e+999)) SELECT sum(x), avg(x), total(x) FROM t1;
 } {Inf Inf Inf -Inf -Inf -Inf}
 
+# 2024-03-21 https://sqlite.org/forum/forumpost/23b8688ef4
+# Another problem with Kahan-Babushka-Neumaier summation and
+# infinities.
+#
+do_execsql_test func-39.101 {
+  WITH RECURSIVE c(n) AS (VALUES(1) UNION ALL SELECT n+1 FROM c WHERE n<1)
+  SELECT sum(1.7976931348623157e308),
+         avg(1.7976931348623157e308),
+         total(1.7976931348623157e308)
+    FROM c;
+} {1.79769313486232e+308 1.79769313486232e+308 1.79769313486232e+308}
+for {set i 2} {$i<10} {incr i} {
+  do_execsql_test func-39.[expr {10*$i+100}] {
+    WITH RECURSIVE c(n) AS (VALUES(1) UNION ALL SELECT n+1 FROM c WHERE n<$i)
+    SELECT sum(1.7976931348623157e308),
+           avg(1.7976931348623157e308),
+           total(1.7976931348623157e308)
+      FROM c;
+  } {Inf Inf Inf}
+}
+
 finish_test