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Add security points in conditions and compounds

--- a/cc1/cc1.h

+++ b/cc1/cc1.h

@@ -4,10 +4,13 @@

 extern void warn(char *fmt, ...);

 extern void unexpected(void);

 extern void softerror(char *fmt, ...);

-extern bool setsafe(uint8_t type);

+extern void setsafe(uint8_t type);

 enum {

-	END_DECL

+	END_DECL,

+	END_LDECL,

+	END_COMP,

+	END_COND

 };

 /* definitions of types */

--- a/cc1/decl.c

+++ b/cc1/decl.c

@@ -1,5 +1,6 @@

 #include <inttypes.h>

+#include <setjmp.h>

 #include <string.h>

 #include "../inc/sizes.h"

@@ -427,12 +428,17 @@

 	Type *tp;

 	Symbol *sym;

 	int8_t sclass, isfun;

+	extern jmp_buf recover;

+	setsafe(END_DECL);

+	setjmp(recover);

 	tp = specifier(&sclass);

 	if (accept(';'))

 		return;

 	do {

+		setsafe(END_LDECL);

+		setjmp(recover);

 		sym = declarator(tp, ID_EXPECTED, NS_IDEN);

 		isfun = sym->type->op == FTN;

@@ -492,9 +498,10 @@

 	int8_t sclass;

 	Symbol *sym;

 	extern Symbol *curfun;

+	extern jmp_buf recover;

-	if (!setsafe(END_DECL))

-		return;

+	setsafe(END_DECL);

+	setjmp(recover);

 	switch (yytoken) {

 	case IDEN: case TYPE: case TYPEIDEN: case SCLASS: case TQUALIFIER:

@@ -502,6 +509,8 @@

 		if (accept(';'))

 			return;

 		do {

+			setsafe(END_LDECL);

+			setjmp(recover);

 			sym = declarator(base, ID_EXPECTED, NS_IDEN);

 			tp = sym->type;

 			sym->isstatic = 1;

--- a/cc1/error.c

+++ b/cc1/error.c

@@ -39,13 +39,10 @@

 	va_end(va);

 }

-bool

+void

 setsafe(uint8_t type)

 {

 	safe = type;

-	if (setjmp(recover))

-		return 0;

-	return 1;

 }

 void

@@ -53,6 +50,7 @@

 {

 	int c;

 	va_list va;

+	extern FILE *yyin;

 	va_start(va, fmt);

 	warn_helper(-1, fmt, va);

@@ -62,12 +60,24 @@

 	c = yytoken;

 	do {

 		switch (safe) {

+		case END_COMP:

+			if (c == '}')

+				goto jump;

+			goto semicolon;

+		case END_COND:

+			if (c == ')')

+				goto jump;

+			break;

+		case END_LDECL:

+			if (c == ',')

+				goto jump;

 		case END_DECL:

+		semicolon:

 			if (c == ';')

 				goto jump;

 			break;

 		}

-	} while ((c = getchar()) != EOF);

+	} while ((c = getc(yyin)) != EOF);

 jump:

 	yytoken = c;

--- a/cc1/lex.c

+++ b/cc1/lex.c

@@ -9,7 +9,7 @@

 #include "../inc/cc.h"

 #include "cc1.h"

-static FILE *yyin;

+FILE *yyin;

 uint8_t lex_ns = NS_IDEN;

 const char *filename;

 unsigned linenum;

@@ -374,11 +374,10 @@

 void

 expect(uint8_t tok)

 {

-	if (yytoken != tok) {

-		softerror("unexpecetd '%s'", yytext);

-		yytoken = tok;

-	}

-	next();

+	if (yytoken != tok)

+		softerror("expected '%c' before '%s'", tok, yytext);

+	else

+		next();

 }

 uint8_t

@@ -406,4 +405,3 @@

 	}

 	linenum = 1;

 }

-

--- a/cc1/stmt.c

+++ b/cc1/stmt.c

@@ -1,6 +1,7 @@

 #include <stddef.h>

 #include <inttypes.h>

+#include <setjmp.h>

 #include <stdio.h>

 #include "../inc/cc.h"

@@ -60,10 +61,16 @@

 static Node *

 condition(void)

 {

+	extern jmp_buf recover;

+	extern Symbol *zero;

 	Node *np;

 	expect('(');

-	np = iszero(expr());

+	setsafe(END_COND);

+	if (!setjmp(recover))

+		np = iszero(expr());

+	else

+		np = symbol(zero);

 	expect(')');

 	return np;

 }

@@ -311,10 +318,13 @@

 void

 compound(Symbol *lbreak, Symbol *lcont, Caselist *lswitch)

 {

+	extern jmp_buf recover;

 	pushctx();

 	expect('{');

 	for (;;) {

+		setsafe(END_COMP);

+		setjmp(recover);

 		switch (yytoken) {

 		case '}':

 			goto end_compound;

@@ -369,4 +379,3 @@

 	}

 	(*fun)(lbreak, lcont, lswitch);

 }

-