Minor improvements to comments in the data structure definitions. No

changes to code.

FossilOrigin-Name: e77ac4050cf6c24118ce2af4c075f60e3eeb2dafe6d222c848bc4e541eef7172

manifest

@@ -1,5 +1,5 @@
-C New\sassert()\sstatements\sto\sprotect\sthe\su1\sand\su2\sunions\sof\sSrcList.
-D 2021-10-07T23:04:50.256
+C Minor\simprovements\sto\scomments\sin\sthe\sdata\sstructure\sdefinitions.\s\sNo\nchanges\sto\scode.
+D 2021-10-08T10:25:06.619
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -554,7 +554,7 @@ F src/shell.c.in ac685e63c506fb2e39375c83347c88bff84dc48fa5d6a59f508d7d67951693a
 F src/sqlite.h.in 4e977a5e2ed1a9e8987ff65a2cab5f99a4298ebf040ea5ff636e1753339ff45a
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h e97f4e9b509408fea4c4e9bef5a41608dfac343b4d3c7a990dedde1e19af9510
-F src/sqliteInt.h d83718ee235209088e809480a1651123f864f8f6a42793877cd8c2c3ba052b60
+F src/sqliteInt.h 1c533af6ddc8bac06db0706698227b1a04d3c25a439dae5f1d72d672e51a6244
 F src/sqliteLimit.h d7323ffea5208c6af2734574bae933ca8ed2ab728083caa117c9738581a31657
 F src/status.c 4b8bc2a6905163a38b739854a35b826c737333fab5b1f8e03fa7eb9a4799c4c1
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
@@ -1928,7 +1928,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 87e2f5eb436fc448427b0e24fb70f29688796b513b8c7b12f1a21540dae1e56d
-R 26f96ed7e6bc8d87135a2e1f26f03c7a
+P 9b91fbcfcc14048f7d0755d47d9b7f9212fa2eaa6f3c04f417fa16c3a47943bf
+R 4b303a4d6767f7ff61406cb5e533618e
 U drh
-Z 1e388ad2186d49d3ab5f000ad284e609
+Z 17855c0746b72f35a62a4e373c2c0159

manifest.uuid

@@ -1 +1 @@
-9b91fbcfcc14048f7d0755d47d9b7f9212fa2eaa6f3c04f417fa16c3a47943bf
+e77ac4050cf6c24118ce2af4c075f60e3eeb2dafe6d222c848bc4e541eef7172

src/sqliteInt.h

@@ -1571,10 +1571,10 @@ struct sqlite3 {
   int nExtension;               /* Number of loaded extensions */
   void **aExtension;            /* Array of shared library handles */
   union {
-    void (*xLegacy)(void*,const char*);     /* Legacy trace function */
-    int (*xV2)(u32,void*,void*,void*);      /* V2 Trace function */
+    void (*xLegacy)(void*,const char*);   /* mTrace==SQLITE_TRACE_LEGACY */
+    int (*xV2)(u32,void*,void*,void*);    /* All other mTrace values */
   } trace;
-  void *pTraceArg;                          /* Argument to the trace function */
+  void *pTraceArg;                        /* Argument to the trace function */
 #ifndef SQLITE_OMIT_DEPRECATED
   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
   void *pProfileArg;                        /* Argument to profile function */
@@ -2717,10 +2717,10 @@ typedef int ynVar;
 ** tree.
 **
 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
-** or TK_STRING), then Expr.token contains the text of the SQL literal. If
-** the expression is a variable (TK_VARIABLE), then Expr.token contains the
+** or TK_STRING), then Expr.u.zToken contains the text of the SQL literal. If
+** the expression is a variable (TK_VARIABLE), then Expr.u.zToken contains the
 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
-** then Expr.token contains the name of the function.
+** then Expr.u.zToken contains the name of the function.
 **
 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
 ** binary operator. Either or both may be NULL.
@@ -2760,7 +2760,7 @@ typedef int ynVar;
 ** help reduce memory requirements, sometimes an Expr object will be
 ** truncated.  And to reduce the number of memory allocations, sometimes
 ** two or more Expr objects will be stored in a single memory allocation,
-** together with Expr.zToken strings.
+** together with Expr.u.zToken strings.
 **
 ** If the EP_Reduced and EP_TokenOnly flags are set when
 ** an Expr object is truncated.  When EP_Reduced is set, then all
@@ -3018,6 +3018,13 @@ struct IdList {
 /*
 ** The SrcItem object represents a single term in the FROM clause of a query.
 ** The SrcList object is mostly an array of SrcItems.
+**
+** Union member validity:
+**
+**    u1.zIndexedBy          fg.isIndexedBy && !fg.isTabFunc
+**    u1.pFuncArg            fg.isTabFunc   && !fg.isIndexedBy
+**    u2.pIBIndex            fg.isIndexedBy && !fg.isCte
+**    u2.pCteUse             fg.isCte       && !fg.isIndexedBy
 */
 struct SrcItem {
   Schema *pSchema;  /* Schema to which this item is fixed */
@@ -3612,6 +3619,8 @@ struct Parse {
 #endif
 };
 
+/* Allowed values for Parse.eParseMode
+*/
 #define PARSE_MODE_NORMAL        0
 #define PARSE_MODE_DECLARE_VTAB  1
 #define PARSE_MODE_RENAME        2