From 7b8799e5ff02184d60df34a034396dc98ac59ed0 Mon Sep 17 00:00:00 2001
From: grischka <grischka>
Date: Tue, 16 Jul 2019 17:30:04 +0200
Subject: [PATCH] tccgen.c: local extern decls: copy s->ref for VT_PTR too

This fixes the issue

    int main() { extern char *x; }
    void main1() { extern char *x; }
    t2.c:5: error: incompatible types for redefinition of 'x'

(reported by Giovanni Mascellani 2019/07/16)
---
 Makefile                                   |  2 +-
 tccgen.c                                   | 28 ++++++++++++----------
 tests/tests2/60_errors_and_warnings.c      | 22 +++++++++++++++++
 tests/tests2/60_errors_and_warnings.expect |  2 ++
 4 files changed, 41 insertions(+), 13 deletions(-)

diff --git a/Makefile b/Makefile
index 1c05e8a0..6c87f010 100644
--- a/Makefile
+++ b/Makefile
@@ -98,7 +98,7 @@ TCC_X += riscv64
 
 # cross libtcc1.a targets to build
 LIBTCC1_X = i386 x86_64 i386-win32 x86_64-win32 x86_64-osx arm arm64 arm-wince
-LIBTCC1_X = riscv64
+LIBTCC1_X += riscv64
 
 PROGS_CROSS = $(foreach X,$(TCC_X),$X-tcc$(EXESUF))
 LIBTCC1_CROSS = $(foreach X,$(LIBTCC1_X),$X-libtcc1.a)
diff --git a/tccgen.c b/tccgen.c
index bb7438bd..237869c8 100644
--- a/tccgen.c
+++ b/tccgen.c
@@ -1096,18 +1096,24 @@ static Sym *sym_copy(Sym *s0, Sym **ps)
     return s;
 }
 
-/* copy a list of syms */
-static void sym_copy_ref(Sym *s0, Sym **ps)
+/* copy s->type.ref to stack 'ps' for VT_FUNC and VT_PTR */
+static void sym_copy_ref(Sym *s, Sym **ps)
 {
-    Sym *s, **sp = &s0->type.ref;
-    for (s = *sp, *sp = NULL; s; s = s->next)
-        sp = &(*sp = sym_copy(s, ps))->next;
+    int bt = s->type.t & VT_BTYPE;
+    if (bt == VT_FUNC || bt == VT_PTR) {
+        Sym **sp = &s->type.ref;
+        for (s = *sp, *sp = NULL; s; s = s->next) {
+            Sym *s2 = sym_copy(s, ps);
+            sp = &(*sp = s2)->next;
+            sym_copy_ref(s2, ps);
+        }
+    }
 }
 
 /* define a new external reference to a symbol 'v' */
 static Sym *external_sym(int v, CType *type, int r, AttributeDef *ad)
 {
-    Sym *s; int bt;
+    Sym *s;
 
     /* look for global symbol */
     s = sym_find(v);
@@ -1121,16 +1127,14 @@ static Sym *external_sym(int v, CType *type, int r, AttributeDef *ad)
         s->a = ad->a;
         s->asm_label = ad->asm_label;
         s->type.ref = type->ref;
-        bt = s->type.t & (VT_BTYPE|VT_ARRAY);
-        /* copy type to the global stack also */
-        if (local_scope && (bt == VT_FUNC || (bt & VT_ARRAY)))
+        /* copy type to the global stack */
+        if (local_stack)
             sym_copy_ref(s, &global_stack);
     } else {
         patch_storage(s, ad, type);
-        bt = s->type.t & VT_BTYPE;
     }
-    /* push variables to local scope if any */
-    if (local_stack && bt != VT_FUNC)
+    /* push variables on local_stack if any */
+    if (local_stack && (s->type.t & VT_BTYPE) != VT_FUNC)
         s = sym_copy(s, &local_stack);
     return s;
 }
diff --git a/tests/tests2/60_errors_and_warnings.c b/tests/tests2/60_errors_and_warnings.c
index b84eec2c..14ff527b 100644
--- a/tests/tests2/60_errors_and_warnings.c
+++ b/tests/tests2/60_errors_and_warnings.c
@@ -273,5 +273,27 @@ int main ()
 int xxx[1] = {1};
 int bar() { P(3, xxx[0]); return 0; }
 
+#elif defined test_var_4
+struct yyy { int y; };
+struct zzz;
+void f1() {
+    extern char *x;
+    extern char **xx;
+    extern struct yyy y;
+    extern struct yyy *yy;
+    extern struct zzz z;
+    extern struct zzz *zz;
+}
+void f2() {
+    extern char *x;
+    extern char **xx;
+    extern struct yyy y;
+    extern struct yyy *yy;
+    extern struct zzz z;
+    extern struct zzz *zz;
+}
+struct yyy y, *yy;
+struct zzz { int z; } z, *zz;
+
 /******************************************************************/
 #endif
diff --git a/tests/tests2/60_errors_and_warnings.expect b/tests/tests2/60_errors_and_warnings.expect
index f252355d..93986d80 100644
--- a/tests/tests2/60_errors_and_warnings.expect
+++ b/tests/tests2/60_errors_and_warnings.expect
@@ -132,3 +132,5 @@ bar  : 3 ; 3
 
 [test_var_3]
 60_errors_and_warnings.c:273: error: incompatible types for redefinition of 'xxx'
+
+[test_var_4]