From 70364d9a8d1c57da490e0187421ae94af42bf579 Mon Sep 17 00:00:00 2001
From: Amine Najahi <address@hidden>
Date: Fri, 11 Mar 2016 17:54:11 +0100
Subject: [PATCH] Fix duplicate case values bug.

---
 tccgen.c | 36 +++++++++++++++++++++++-------------
 1 file changed, 23 insertions(+), 13 deletions(-)

diff --git a/tccgen.c b/tccgen.c
index 3cd28ed..ef4b2e6 100644
--- a/tccgen.c
+++ b/tccgen.c
@@ -80,7 +80,7 @@ static int parse_btype(CType *type, AttributeDef *ad);
 static void type_decl(CType *type, AttributeDef *ad, int *v, int td);
 static void parse_expr_type(CType *type);
 static void decl_initializer(CType *type, Section *sec, unsigned long c, int first, int size_only);
-static void block(int *bsym, int *csym, int *case_sym, int *def_sym, int case_reg, int is_expr);
+static void block(int *bsym, int *csym, int *case_sym, int *def_sym, int case_reg, int is_expr, void*** cases, int* cases_cnt);
 static void decl_initializer_alloc(CType *type, AttributeDef *ad, int r, int has_init, int v, int scope);
 static int decl0(int l, int is_for_loop_init);
 static void expr_eq(void);
@@ -3848,7 +3848,7 @@ ST_FUNC void unary(void)
             save_regs(0); 
             /* statement expression : we do not accept break/continue
                inside as GCC does */
-            block(NULL, NULL, NULL, NULL, 0, 1);
+            block(NULL, NULL, NULL, NULL, 0, 1, NULL, 0);
             skip(')');
         } else {
             gexpr();
@@ -4816,7 +4816,7 @@ static void label_or_decl(int l)
 }
 
 static void block(int *bsym, int *csym, int *case_sym, int *def_sym, 
-                  int case_reg, int is_expr)
+                  int case_reg, int is_expr, void*** cases, int* cases_cnt)
 {
     int a, b, c, d;
     Sym *s, *frame_bottom;
@@ -4842,13 +4842,13 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
         gexpr();
         skip(')');
         a = gvtst(1, 0);
-        block(bsym, csym, case_sym, def_sym, case_reg, 0);
+        block(bsym, csym, case_sym, def_sym, case_reg, 0, cases, cases_cnt);
         c = tok;
         if (c == TOK_ELSE) {
             next();
             d = gjmp(0);
             gsym(a);
-            block(bsym, csym, case_sym, def_sym, case_reg, 0);
+            block(bsym, csym, case_sym, def_sym, case_reg, 0, cases, cases_cnt);
             gsym(d); /* patch else jmp */
         } else
             gsym(a);
@@ -4861,7 +4861,7 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
         skip(')');
         a = gvtst(1, 0);
         b = 0;
-        block(&a, &b, case_sym, def_sym, case_reg, 0);
+        block(&a, &b, case_sym, def_sym, case_reg, 0, cases, cases_cnt);
         gjmp_addr(d);
         gsym(a);
         gsym_addr(b, d);
@@ -4898,7 +4898,7 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
             if (tok != '}') {
                 if (is_expr)
                     vpop();
-                block(bsym, csym, case_sym, def_sym, case_reg, is_expr);
+                block(bsym, csym, case_sym, def_sym, case_reg, is_expr, cases, cases_cnt);
             }
         }
         /* pop locally defined labels */
@@ -5053,7 +5053,7 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
             gsym(e);
         }
         skip(')');
-        block(&a, &b, case_sym, def_sym, case_reg, 0);
+        block(&a, &b, case_sym, def_sym, case_reg, 0, cases, cases_cnt);
         gjmp_addr(c);
         gsym(a);
         gsym_addr(b, c);
@@ -5066,7 +5066,7 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
         b = 0;
         d = ind;
         vla_sp_restore();
-        block(&a, &b, case_sym, def_sym, case_reg, 0);
+        block(&a, &b, case_sym, def_sym, case_reg, 0, cases, cases_cnt);
         skip(TOK_WHILE);
         skip('(');
         gsym(b);
@@ -5078,6 +5078,8 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
         skip(';');
     } else
     if (tok == TOK_SWITCH) {
+        void** new_cases = NULL;
+        int new_cases_cnt = 0;
         next();
         skip('(');
         gexpr();
@@ -5088,7 +5090,8 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
         a = 0;
         b = gjmp(0); /* jump to first case */
         c = 0;
-        block(&a, csym, &b, &c, case_reg, 0);
+        block(&a, csym, &b, &c, case_reg, 0, &new_cases, &new_cases_cnt);
+        dynarray_reset(&new_cases, &new_cases_cnt);
         /* if no default, jmp after switch */
         if (c == 0)
             c = ind;
@@ -5098,11 +5101,18 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
         gsym(a);
     } else
     if (tok == TOK_CASE) {
-        int v1, v2;
+        int i, v1, v2, *case_value;
+        void** pp;
         if (!case_sym)
             expect("switch");
         next();
         v1 = expr_const();
+        for (i = 0, pp=*cases; i < *cases_cnt; ++i, ++pp)
+          if (v1 == **(int **) pp)
+            tcc_error("duplicate case value '%d'", v1);
+        case_value = tcc_malloc ( sizeof ( int ) );
+        *case_value = v1;
+        dynarray_add(cases, cases_cnt, case_value);
         v2 = v1;
         if (gnu_ext && tok == TOK_DOTS) {
             next();
@@ -5197,7 +5207,7 @@ static void block(int *bsym, int *csym, int *case_sym, int *def_sym,
             } else {
                 if (is_expr)
                     vpop();
-                block(bsym, csym, case_sym, def_sym, case_reg, is_expr);
+                block(bsym, csym, case_sym, def_sym, case_reg, is_expr, cases, cases_cnt);
             }
         } else {
             /* expression case */
@@ -6105,7 +6115,7 @@ static void gen_function(Sym *sym)
     }
 #endif
     rsym = 0;
-    block(NULL, NULL, NULL, NULL, 0, 0);
+    block(NULL, NULL, NULL, NULL, 0, 0, NULL, 0);
     gsym(rsym);
     gfunc_epilog();
     cur_text_section->data_offset = ind;
-- 
2.7.0