*** a/src/backend/commands/tablecmds.c
--- b/src/backend/commands/tablecmds.c
***************
*** 82,87 ****
--- 82,88 ----
  #include "storage/smgr.h"
  #include "utils/acl.h"
  #include "utils/builtins.h"
+ #include "utils/elog.h"
  #include "utils/fmgroids.h"
  #include "utils/inval.h"
  #include "utils/lsyscache.h"
***************
*** 309,314 **** static void ATController(AlterTableStmt *parsetree,
--- 310,316 ----
  			 Relation rel, List *cmds, bool recurse, LOCKMODE lockmode);
  static void ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
  		  bool recurse, bool recursing, LOCKMODE lockmode);
+ static void ATRewriteSubcommandErrorCallback(void *arg);
  static void ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode);
  static void ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
  		  AlterTableCmd *cmd, LOCKMODE lockmode);
***************
*** 3373,3378 **** ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
--- 3375,3399 ----
  	tab->subcmds[pass] = lappend(tab->subcmds[pass], cmd);
  }
  
+ static void
+ ATRewriteSubcommandErrorCallback(void *arg)
+ {
+ 	AlterTableCmd *subcmd = (AlterTableCmd *) arg;
+ 	
+ 	switch (subcmd->subtype)
+ 	{
+ 		case AT_ReAddIndex:
+ 			errcontext("while rebuilding index %s", subcmd->name);
+ 			break;
+ 		case AT_ReAddConstraint:
+ 			errcontext("while rebuilding constraint %s", subcmd->name);
+ 			break;
+ 		default:
+ 			/* keep compiler quiet */
+ 			(void) 0;
+ 	}
+ }
+ 
  /*
   * ATRewriteCatalogs
   *
***************
*** 3402,3407 **** ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode)
--- 3423,3429 ----
  			List	   *subcmds = tab->subcmds[pass];
  			Relation	rel;
  			ListCell   *lcmd;
+ 			ErrorContextCallback errcallback;
  
  			if (subcmds == NIL)
  				continue;
***************
*** 3411,3418 **** ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode)
  			 */
  			rel = relation_open(tab->relid, NoLock);
  
  			foreach(lcmd, subcmds)
! 				ATExecCmd(wqueue, tab, rel, (AlterTableCmd *) lfirst(lcmd), lockmode);
  
  			/*
  			 * After the ALTER TYPE pass, do cleanup work (this is not done in
--- 3433,3451 ----
  			 */
  			rel = relation_open(tab->relid, NoLock);
  
+ 			errcallback.callback = ATRewriteSubcommandErrorCallback;
+ 			errcallback.previous = error_context_stack;
+ 			error_context_stack = &errcallback;
+ 
  			foreach(lcmd, subcmds)
! 			{
! 				AlterTableCmd *subcmd = (AlterTableCmd *) lfirst(lcmd);
! 
! 				errcallback.arg = subcmd;
! 				ATExecCmd(wqueue, tab, rel, subcmd, lockmode);
! 			}
! 
! 			error_context_stack = errcallback.previous;
  
  			/*
  			 * After the ALTER TYPE pass, do cleanup work (this is not done in
***************
*** 8682,8687 **** ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
--- 8715,8721 ----
  
  			newcmd = makeNode(AlterTableCmd);
  			newcmd->subtype = AT_ReAddIndex;
+ 			newcmd->name = stmt->idxname;
  			newcmd->def = (Node *) stmt;
  			tab->subcmds[AT_PASS_OLD_INDEX] =
  				lappend(tab->subcmds[AT_PASS_OLD_INDEX], newcmd);
***************
*** 8712,8717 **** ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
--- 8746,8752 ----
  													 RelationRelationId, 0);
  
  					cmd->subtype = AT_ReAddIndex;
+ 					cmd->name = indstmt->idxname;
  					tab->subcmds[AT_PASS_OLD_INDEX] =
  						lappend(tab->subcmds[AT_PASS_OLD_INDEX], cmd);
  
***************
*** 8734,8739 **** ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
--- 8769,8775 ----
  						!rewrite && tab->rewrite == 0)
  						TryReuseForeignKey(oldId, con);
  					cmd->subtype = AT_ReAddConstraint;
+ 					cmd->name = con->conname;
  					tab->subcmds[AT_PASS_OLD_CONSTR] =
  						lappend(tab->subcmds[AT_PASS_OLD_CONSTR], cmd);
  
*** a/src/test/regress/expected/alter_table.out
--- b/src/test/regress/expected/alter_table.out
***************
*** 1737,1742 **** alter table anothertab alter column atcol1 type boolean
--- 1737,1743 ----
          using case when atcol1 % 2 = 0 then true else false end; -- fails
  ERROR:  operator does not exist: boolean <= integer
  HINT:  No operator matches the given name and argument type(s). You might need to add explicit type casts.
+ CONTEXT:  while rebuilding constraint anothertab_chk
  alter table anothertab drop constraint anothertab_chk;
  alter table anothertab drop constraint anothertab_chk; -- fails
  ERROR:  constraint "anothertab_chk" of relation "anothertab" does not exist