Go back to returning int from ereport auxiliary functions.

This reverts the parts of commit 17a28b0364
that changed ereport's auxiliary functions from returning dummy integer
values to returning void.  It turns out that a minority of compilers
complain (not entirely unreasonably) about constructs such as

	(condition) ? errdetail(...) : 0

if errdetail() returns void rather than int.  We could update those
call sites to say "(void) 0" perhaps, but the expectation for this
patch set was that ereport callers would not have to change anything.
And this aspect of the patch set was already the most invasive and
least compelling part of it, so let's just drop it.

Per buildfarm.

Discussion: https://postgr.es/m/CA+fd4k6N8EjNvZpM8nme+y+05mz-SM8Z_BgkixzkA34R+ej0Kw@mail.gmail.com

src/backend/executor/execUtils.c

@@ -832,21 +832,21 @@ UpdateChangedParamSet(PlanState *node, Bitmapset *newchg)
  * normal non-error case: computing character indexes would be much more
  * expensive than storing token offsets.)
  */
-void
+int
 executor_errposition(EState *estate, int location)
 {
 	int			pos;
 
 	/* No-op if location was not provided */
 	if (location < 0)
-		return;
+		return 0;
 	/* Can't do anything if source text is not available */
 	if (estate == NULL || estate->es_sourceText == NULL)
-		return;
+		return 0;
 	/* Convert offset to character number */
 	pos = pg_mbstrlen_with_len(estate->es_sourceText, location) + 1;
 	/* And pass it to the ereport mechanism */
-	errposition(pos);
+	return errposition(pos);
 }
 
 /*

src/backend/parser/parse_coerce.c

@@ -1246,15 +1246,15 @@ coerce_to_specific_type(ParseState *pstate, Node *node,
  * XXX possibly this is more generally useful than coercion errors;
  * if so, should rename and place with parser_errposition.
  */
-void
+int
 parser_coercion_errposition(ParseState *pstate,
 							int coerce_location,
 							Node *input_expr)
 {
 	if (coerce_location >= 0)
-		parser_errposition(pstate, coerce_location);
+		return parser_errposition(pstate, coerce_location);
 	else
-		parser_errposition(pstate, exprLocation(input_expr));
+		return parser_errposition(pstate, exprLocation(input_expr));
 }
 
 

src/backend/parser/parse_node.c

@@ -106,21 +106,21 @@ free_parsestate(ParseState *pstate)
  * normal non-error case: computing character indexes would be much more
  * expensive than storing token offsets.)
  */
-void
+int
 parser_errposition(ParseState *pstate, int location)
 {
 	int			pos;
 
 	/* No-op if location was not provided */
 	if (location < 0)
-		return;
+		return 0;
 	/* Can't do anything if source text is not available */
 	if (pstate == NULL || pstate->p_sourcetext == NULL)
-		return;
+		return 0;
 	/* Convert offset to character number */
 	pos = pg_mbstrlen_with_len(pstate->p_sourcetext, location) + 1;
 	/* And pass it to the ereport mechanism */
-	errposition(pos);
+	return errposition(pos);
 }
 
 

src/backend/parser/scan.l

@@ -1076,18 +1076,18 @@ other			.
  * (essentially, scan.l, parser.c, and gram.y), since it requires the
  * yyscanner struct to still be available.
  */
-void
+int
 scanner_errposition(int location, core_yyscan_t yyscanner)
 {
 	int			pos;
 
 	if (location < 0)
-		return;				/* no-op if location is unknown */
+		return 0;				/* no-op if location is unknown */
 
 	/* Convert byte offset to character number */
 	pos = pg_mbstrlen_with_len(yyextra->scanbuf, location) + 1;
 	/* And pass it to the ereport mechanism */
-	errposition(pos);
+	return errposition(pos);
 }
 
 /*

src/backend/storage/ipc/dsm_impl.c

@@ -92,7 +92,7 @@ static bool dsm_impl_mmap(dsm_op op, dsm_handle handle, Size request_size,
 						  void **impl_private, void **mapped_address,
 						  Size *mapped_size, int elevel);
 #endif
-static void errcode_for_dynamic_shared_memory(void);
+static int	errcode_for_dynamic_shared_memory(void);
 
 const struct config_enum_entry dynamic_shared_memory_options[] = {
 #ifdef USE_DSM_POSIX
@@ -1030,11 +1030,11 @@ dsm_impl_unpin_segment(dsm_handle handle, void **impl_private)
 	}
 }
 
-static void
+static int
 errcode_for_dynamic_shared_memory(void)
 {
 	if (errno == EFBIG || errno == ENOMEM)
-		errcode(ERRCODE_OUT_OF_MEMORY);
+		return errcode(ERRCODE_OUT_OF_MEMORY);
 	else
-		errcode_for_file_access();
+		return errcode_for_file_access();
 }

src/backend/utils/adt/jsonfuncs.c

@@ -329,7 +329,7 @@ typedef struct JsObject
 			hash_destroy((jso)->val.json_hash); \
 	} while (0)
 
-static void report_json_context(JsonLexContext *lex);
+static int	report_json_context(JsonLexContext *lex);
 
 /* semantic action functions for json_object_keys */
 static void okeys_object_field_start(void *state, char *fname, bool isnull);
@@ -631,7 +631,7 @@ json_ereport_error(JsonParseErrorType error, JsonLexContext *lex)
  * The return value isn't meaningful, but we make it non-void so that this
  * can be invoked inside ereport().
  */
-static void
+static int
 report_json_context(JsonLexContext *lex)
 {
 	const char *context_start;
@@ -689,8 +689,8 @@ report_json_context(JsonLexContext *lex)
 	prefix = (context_start > line_start) ? "..." : "";
 	suffix = (lex->token_type != JSON_TOKEN_END && context_end - lex->input < lex->input_length && *context_end != '\n' && *context_end != '\r') ? "..." : "";
 
-	errcontext("JSON data, line %d: %s%s%s",
-			   line_number, prefix, ctxt, suffix);
+	return errcontext("JSON data, line %d: %s%s%s",
+					  line_number, prefix, ctxt, suffix);
 }
 
 

src/backend/utils/error/elog.c

@@ -606,7 +606,7 @@ errfinish(const char *filename, int lineno, const char *funcname)
  *
  * The code is expected to be represented as per MAKE_SQLSTATE().
  */
-void
+int
 errcode(int sqlerrcode)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -615,6 +615,8 @@ errcode(int sqlerrcode)
 	CHECK_STACK_DEPTH();
 
 	edata->sqlerrcode = sqlerrcode;
+
+	return 0;					/* return value does not matter */
 }
 
 
@@ -627,7 +629,7 @@ errcode(int sqlerrcode)
  * NOTE: the primary error message string should generally include %m
  * when this is used.
  */
-void
+int
 errcode_for_file_access(void)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -685,6 +687,8 @@ errcode_for_file_access(void)
 			edata->sqlerrcode = ERRCODE_INTERNAL_ERROR;
 			break;
 	}
+
+	return 0;					/* return value does not matter */
 }
 
 /*
@@ -696,7 +700,7 @@ errcode_for_file_access(void)
  * NOTE: the primary error message string should generally include %m
  * when this is used.
  */
-void
+int
 errcode_for_socket_access(void)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -719,6 +723,8 @@ errcode_for_socket_access(void)
 			edata->sqlerrcode = ERRCODE_INTERNAL_ERROR;
 			break;
 	}
+
+	return 0;					/* return value does not matter */
 }
 
 
@@ -814,7 +820,7 @@ errcode_for_socket_access(void)
  * Note: no newline is needed at the end of the fmt string, since
  * ereport will provide one for the output methods that need it.
  */
-void
+int
 errmsg(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -829,13 +835,14 @@ errmsg(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 /*
  * Add a backtrace to the containing ereport() call.  This is intended to be
  * added temporarily during debugging.
  */
-void
+int
 errbacktrace(void)
 {
 	ErrorData   *edata = &errordata[errordata_stack_depth];
@@ -849,6 +856,8 @@ errbacktrace(void)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+
+	return 0;
 }
 
 /*
@@ -898,7 +907,7 @@ set_backtrace(ErrorData *edata, int num_skip)
  * the message because the translation would fail and result in infinite
  * error recursion.
  */
-void
+int
 errmsg_internal(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -913,6 +922,7 @@ errmsg_internal(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 
@@ -920,7 +930,7 @@ errmsg_internal(const char *fmt,...)
  * errmsg_plural --- add a primary error message text to the current error,
  * with support for pluralization of the message text
  */
-void
+int
 errmsg_plural(const char *fmt_singular, const char *fmt_plural,
 			  unsigned long n,...)
 {
@@ -936,13 +946,14 @@ errmsg_plural(const char *fmt_singular, const char *fmt_plural,
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 
 /*
  * errdetail --- add a detail error message text to the current error
  */
-void
+int
 errdetail(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -956,6 +967,7 @@ errdetail(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 
@@ -968,7 +980,7 @@ errdetail(const char *fmt,...)
  * messages that seem not worth translating for one reason or another
  * (typically, that they don't seem to be useful to average users).
  */
-void
+int
 errdetail_internal(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -982,13 +994,14 @@ errdetail_internal(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 
 /*
  * errdetail_log --- add a detail_log error message text to the current error
  */
-void
+int
 errdetail_log(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1002,13 +1015,14 @@ errdetail_log(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 /*
  * errdetail_log_plural --- add a detail_log error message text to the current error
  * with support for pluralization of the message text
  */
-void
+int
 errdetail_log_plural(const char *fmt_singular, const char *fmt_plural,
 					 unsigned long n,...)
 {
@@ -1023,6 +1037,7 @@ errdetail_log_plural(const char *fmt_singular, const char *fmt_plural,
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 
@@ -1030,7 +1045,7 @@ errdetail_log_plural(const char *fmt_singular, const char *fmt_plural,
  * errdetail_plural --- add a detail error message text to the current error,
  * with support for pluralization of the message text
  */
-void
+int
 errdetail_plural(const char *fmt_singular, const char *fmt_plural,
 				 unsigned long n,...)
 {
@@ -1045,13 +1060,14 @@ errdetail_plural(const char *fmt_singular, const char *fmt_plural,
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 
 /*
  * errhint --- add a hint error message text to the current error
  */
-void
+int
 errhint(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1065,6 +1081,7 @@ errhint(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 
@@ -1075,7 +1092,7 @@ errhint(const char *fmt,...)
  * context information.  We assume earlier calls represent more-closely-nested
  * states.
  */
-void
+int
 errcontext_msg(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1089,6 +1106,7 @@ errcontext_msg(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	return 0;					/* return value does not matter */
 }
 
 /*
@@ -1100,7 +1118,7 @@ errcontext_msg(const char *fmt,...)
  * a set_errcontext_domain() call to specify the domain.  This is usually
  * done transparently by the errcontext() macro.
  */
-void
+int
 set_errcontext_domain(const char *domain)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1110,6 +1128,8 @@ set_errcontext_domain(const char *domain)
 
 	/* the default text domain is the backend's */
 	edata->context_domain = domain ? domain : PG_TEXTDOMAIN("postgres");
+
+	return 0;					/* return value does not matter */
 }
 
 
@@ -1118,7 +1138,7 @@ set_errcontext_domain(const char *domain)
  *
  * This should be called if the message text already includes the statement.
  */
-void
+int
 errhidestmt(bool hide_stmt)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1127,6 +1147,8 @@ errhidestmt(bool hide_stmt)
 	CHECK_STACK_DEPTH();
 
 	edata->hide_stmt = hide_stmt;
+
+	return 0;					/* return value does not matter */
 }
 
 /*
@@ -1135,7 +1157,7 @@ errhidestmt(bool hide_stmt)
  * This should only be used for verbose debugging messages where the repeated
  * inclusion of context would bloat the log volume too much.
  */
-void
+int
 errhidecontext(bool hide_ctx)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1144,6 +1166,8 @@ errhidecontext(bool hide_ctx)
 	CHECK_STACK_DEPTH();
 
 	edata->hide_ctx = hide_ctx;
+
+	return 0;					/* return value does not matter */
 }
 
 
@@ -1154,7 +1178,7 @@ errhidecontext(bool hide_ctx)
  * name appear in messages sent to old-protocol clients.  Note that the
  * passed string is expected to be a non-freeable constant string.
  */
-void
+int
 errfunction(const char *funcname)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1164,12 +1188,14 @@ errfunction(const char *funcname)
 
 	edata->funcname = funcname;
 	edata->show_funcname = true;
+
+	return 0;					/* return value does not matter */
 }
 
 /*
  * errposition --- add cursor position to the current error
  */
-void
+int
 errposition(int cursorpos)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1178,12 +1204,14 @@ errposition(int cursorpos)
 	CHECK_STACK_DEPTH();
 
 	edata->cursorpos = cursorpos;
+
+	return 0;					/* return value does not matter */
 }
 
 /*
  * internalerrposition --- add internal cursor position to the current error
  */
-void
+int
 internalerrposition(int cursorpos)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1192,6 +1220,8 @@ internalerrposition(int cursorpos)
 	CHECK_STACK_DEPTH();
 
 	edata->internalpos = cursorpos;
+
+	return 0;					/* return value does not matter */
 }
 
 /*
@@ -1201,7 +1231,7 @@ internalerrposition(int cursorpos)
  * is intended for use in error callback subroutines that are editorializing
  * on the layout of the error report.
  */
-void
+int
 internalerrquery(const char *query)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1217,6 +1247,8 @@ internalerrquery(const char *query)
 
 	if (query)
 		edata->internalquery = MemoryContextStrdup(edata->assoc_context, query);
+
+	return 0;					/* return value does not matter */
 }
 
 /*
@@ -1229,7 +1261,7 @@ internalerrquery(const char *query)
  * Most potential callers should not use this directly, but instead prefer
  * higher-level abstractions, such as errtablecol() (see relcache.c).
  */
-void
+int
 err_generic_string(int field, const char *str)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
@@ -1258,6 +1290,8 @@ err_generic_string(int field, const char *str)
 			elog(ERROR, "unsupported ErrorData field id: %d", field);
 			break;
 	}
+
+	return 0;					/* return value does not matter */
 }
 
 /*

src/include/executor/executor.h

@@ -546,7 +546,7 @@ exec_rt_fetch(Index rti, EState *estate)
 
 extern Relation ExecGetRangeTableRelation(EState *estate, Index rti);
 
-extern void executor_errposition(EState *estate, int location);
+extern int	executor_errposition(EState *estate, int location);
 
 extern void RegisterExprContextCallback(ExprContext *econtext,
 										ExprContextCallbackFunction function,

src/include/parser/parse_coerce.h

@@ -61,7 +61,7 @@ extern Node *coerce_to_specific_type_typmod(ParseState *pstate, Node *node,
 											Oid targetTypeId, int32 targetTypmod,
 											const char *constructName);
 
-extern void parser_coercion_errposition(ParseState *pstate,
+extern int	parser_coercion_errposition(ParseState *pstate,
 										int coerce_location,
 										Node *input_expr);
 

src/include/parser/parse_node.h

@@ -307,7 +307,7 @@ typedef struct ParseCallbackState
 
 extern ParseState *make_parsestate(ParseState *parentParseState);
 extern void free_parsestate(ParseState *pstate);
-extern void parser_errposition(ParseState *pstate, int location);
+extern int	parser_errposition(ParseState *pstate, int location);
 
 extern void setup_parser_errposition_callback(ParseCallbackState *pcbstate,
 											  ParseState *pstate, int location);

src/include/parser/scanner.h

@@ -140,7 +140,7 @@ extern core_yyscan_t scanner_init(const char *str,
 extern void scanner_finish(core_yyscan_t yyscanner);
 extern int	core_yylex(core_YYSTYPE *lvalp, YYLTYPE *llocp,
 					   core_yyscan_t yyscanner);
-extern void scanner_errposition(int location, core_yyscan_t yyscanner);
+extern int	scanner_errposition(int location, core_yyscan_t yyscanner);
 extern void setup_scanner_errposition_callback(ScannerCallbackState *scbstate,
 											   core_yyscan_t yyscanner,
 											   int location);

src/include/utils/elog.h

@@ -149,30 +149,30 @@
 extern bool errstart(int elevel, const char *domain);
 extern void errfinish(const char *filename, int lineno, const char *funcname);
 
-extern void errcode(int sqlerrcode);
+extern int	errcode(int sqlerrcode);
 
-extern void errcode_for_file_access(void);
-extern void errcode_for_socket_access(void);
+extern int	errcode_for_file_access(void);
+extern int	errcode_for_socket_access(void);
 
-extern void errmsg(const char *fmt,...) pg_attribute_printf(1, 2);
-extern void errmsg_internal(const char *fmt,...) pg_attribute_printf(1, 2);
+extern int	errmsg(const char *fmt,...) pg_attribute_printf(1, 2);
+extern int	errmsg_internal(const char *fmt,...) pg_attribute_printf(1, 2);
 
-extern void errmsg_plural(const char *fmt_singular, const char *fmt_plural,
+extern int	errmsg_plural(const char *fmt_singular, const char *fmt_plural,
 						  unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
 
-extern void errdetail(const char *fmt,...) pg_attribute_printf(1, 2);
-extern void errdetail_internal(const char *fmt,...) pg_attribute_printf(1, 2);
+extern int	errdetail(const char *fmt,...) pg_attribute_printf(1, 2);
+extern int	errdetail_internal(const char *fmt,...) pg_attribute_printf(1, 2);
 
-extern void errdetail_log(const char *fmt,...) pg_attribute_printf(1, 2);
+extern int	errdetail_log(const char *fmt,...) pg_attribute_printf(1, 2);
 
-extern void errdetail_log_plural(const char *fmt_singular,
+extern int	errdetail_log_plural(const char *fmt_singular,
 								 const char *fmt_plural,
 								 unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
 
-extern void errdetail_plural(const char *fmt_singular, const char *fmt_plural,
+extern int	errdetail_plural(const char *fmt_singular, const char *fmt_plural,
 							 unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
 
-extern void errhint(const char *fmt,...) pg_attribute_printf(1, 2);
+extern int	errhint(const char *fmt,...) pg_attribute_printf(1, 2);
 
 /*
  * errcontext() is typically called in error context callback functions, not
@@ -184,22 +184,22 @@ extern void errhint(const char *fmt,...) pg_attribute_printf(1, 2);
  */
 #define errcontext	set_errcontext_domain(TEXTDOMAIN),	errcontext_msg
 
-extern void set_errcontext_domain(const char *domain);
+extern int	set_errcontext_domain(const char *domain);
 
-extern void errcontext_msg(const char *fmt,...) pg_attribute_printf(1, 2);
+extern int	errcontext_msg(const char *fmt,...) pg_attribute_printf(1, 2);
 
-extern void errhidestmt(bool hide_stmt);
-extern void errhidecontext(bool hide_ctx);
+extern int	errhidestmt(bool hide_stmt);
+extern int	errhidecontext(bool hide_ctx);
 
-extern void errbacktrace(void);
+extern int	errbacktrace(void);
 
-extern void errfunction(const char *funcname);
-extern void errposition(int cursorpos);
+extern int	errfunction(const char *funcname);
+extern int	errposition(int cursorpos);
 
-extern void internalerrposition(int cursorpos);
-extern void internalerrquery(const char *query);
+extern int	internalerrposition(int cursorpos);
+extern int	internalerrquery(const char *query);
 
-extern void err_generic_string(int field, const char *str);
+extern int	err_generic_string(int field, const char *str);
 
 extern int	geterrcode(void);
 extern int	geterrposition(void);

src/pl/plpgsql/src/pl_scanner.c

@@ -468,20 +468,20 @@ plpgsql_peek2(int *tok1_p, int *tok2_p, int *tok1_loc, int *tok2_loc)
  * parsing of a plpgsql function, since it requires the scanorig string
  * to still be available.
  */
-void
+int
 plpgsql_scanner_errposition(int location)
 {
 	int			pos;
 
 	if (location < 0 || scanorig == NULL)
-		return;					/* no-op if location is unknown */
+		return 0;				/* no-op if location is unknown */
 
 	/* Convert byte offset to character number */
 	pos = pg_mbstrlen_with_len(scanorig, location) + 1;
 	/* And pass it to the ereport mechanism */
 	(void) internalerrposition(pos);
 	/* Also pass the function body string */
-	internalerrquery(scanorig);
+	return internalerrquery(scanorig);
 }
 
 /*

src/pl/plpgsql/src/plpgsql.h

@@ -1319,7 +1319,7 @@ extern void plpgsql_append_source_text(StringInfo buf,
 extern int	plpgsql_peek(void);
 extern void plpgsql_peek2(int *tok1_p, int *tok2_p, int *tok1_loc,
 						  int *tok2_loc);
-extern void plpgsql_scanner_errposition(int location);
+extern int	plpgsql_scanner_errposition(int location);
 extern void plpgsql_yyerror(const char *message) pg_attribute_noreturn();
 extern int	plpgsql_location_to_lineno(int location);
 extern int	plpgsql_latest_lineno(void);