From b7ca74577b56190954eb6eeda8c22996b877f3c5 Mon Sep 17 00:00:00 2001
From: Michael Matz <matz@suse.de>
Date: Mon, 1 Aug 2016 22:55:07 +0200
Subject: [PATCH] struct-init: Allow member initialization from qualified
 lvalues

See testcase.
---
 tccgen.c                           |  5 ++++-
 tests/tests2/86-struct-init.c      | 28 +++++++++++++++++++++++++---
 tests/tests2/86-struct-init.expect |  4 ++++
 3 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/tccgen.c b/tccgen.c
index cb7e221b..a833b177 100644
--- a/tccgen.c
+++ b/tccgen.c
@@ -6012,7 +6012,10 @@ static void decl_initializer(CType *type, Section *sec, unsigned long c,
 
     if (have_elem &&
 	!(type->t & VT_ARRAY) &&
-	is_compatible_types(type, &vtop->type)) {
+	/* Use i_c_parameter_t, to strip toplevel qualifiers.
+	   The source type might have VT_CONSTANT set, which is
+	   of course assignable to a non-const elements.  */
+	is_compatible_parameter_types(type, &vtop->type)) {
         init_putv(type, sec, c);
     } else if (type->t & VT_ARRAY) {
         s = type->ref;
diff --git a/tests/tests2/86-struct-init.c b/tests/tests2/86-struct-init.c
index 6749f984..6ce4e24b 100644
--- a/tests/tests2/86-struct-init.c
+++ b/tests/tests2/86-struct-init.c
@@ -96,6 +96,19 @@ struct Anon gan = { 10, 11 }; // ... which makes it available here.
 union UV2 guv4 = {{4,3}};     // and the other inits from above as well
 */
 
+struct in6_addr {
+    union {
+	u8 u6_addr8[16];
+	unsigned short u6_addr16[8];
+    } u;
+};
+struct flowi6 {
+    struct in6_addr saddr, daddr;
+};
+struct pkthdr {
+    struct in6_addr daddr, saddr;
+};
+struct pkthdr phdr = { { { 6,5,4,3 } }, { { 9,8,7,6 } } };
 #include <stdio.h>
 void print_ (const char *name, const u8 *p, long size)
 {
@@ -107,7 +120,7 @@ void print_ (const char *name, const u8 *p, long size)
 }
 #define print(x) print_(#x, (u8*)&x, sizeof (x))
 #if 1
-void foo (struct W *w)
+void foo (struct W *w, struct pkthdr *phdr_)
 {
   struct S ls = {1, 2, 3, 4};
   struct S ls2 = {1, 2, {3, 4}};
@@ -115,6 +128,9 @@ void foo (struct W *w)
   struct U lu = {3, 5,6,7,8, 4, "huhu", 43};
   struct U lu1 = {3, ls, 4, {"huhu", 43}};
   struct U lu2 = {3, (ls), 4, {"huhu", 43}};
+  const struct S *pls = &ls;
+  struct S ls21 = *pls;
+  struct U lu22 = {3, *pls, 4, {"huhu", 43}};
   /* Incomplete bracing.  */
   struct U lu21 = {3, ls, 4, "huhu", 43};
   /* Optional braces around scalar initializers.  Accepted, but with
@@ -129,20 +145,25 @@ void foo (struct W *w)
   /* Compund literal */
   struct V lv2 = {(struct S)w->t.s, {"hihi", 47}, 48};
   /* Parens around compound literal */
-  struct V lv3 = {((struct S){7,8,{9,10}}), w->t.t, 50};
+  struct V lv3 = {((struct S){7,8,{9,10}}), ((const struct W *)w)->t.t, 50};
+  const struct pkthdr *phdr = phdr_;
+  struct flowi6 flow = { .daddr = phdr->daddr, .saddr = phdr->saddr };
   print(ls);
   print(ls2);
   print(lt);
   print(lu);
   print(lu1);
   print(lu2);
+  print(ls21);
   print(lu21);
+  print(lu22);
   print(lu3);
   print(lu4);
   print(ls3);
   print(lv);
   print(lv2);
   print(lv3);
+  print(flow);
 }
 #endif
 
@@ -167,7 +188,8 @@ int main()
   print(guv.b);
   print(guv2);
   print(guv3);
-  foo(&gw);
+  print(phdr);
+  foo(&gw, &phdr);
   //printf("q: %s\n", q);
   return 0;
 }
diff --git a/tests/tests2/86-struct-init.expect b/tests/tests2/86-struct-init.expect
index a5333dce..b827ec45 100644
--- a/tests/tests2/86-struct-init.expect
+++ b/tests/tests2/86-struct-init.expect
@@ -17,16 +17,20 @@ guv: 6 5 0 0
 guv.b: 5
 guv2: 8 7 0 0
 guv3: 7 8 0 0
+phdr: 6 5 4 3 0 0 0 0 0 0 0 0 0 0 0 0 9 8 7 6 0 0 0 0 0 0 0 0 0 0 0 0
 ls: 1 2 3 4
 ls2: 1 2 3 4
 lt: 68 65 6c 6c 6f 0 0 0 0 0 0 0 0 0 0 0 2a
 lu: 3 5 6 7 8 4 68 75 68 75 0 0 0 0 0 0 0 0 0 0 0 0 2b
 lu1: 3 1 2 3 4 4 68 75 68 75 0 0 0 0 0 0 0 0 0 0 0 0 2b
 lu2: 3 1 2 3 4 4 68 75 68 75 0 0 0 0 0 0 0 0 0 0 0 0 2b
+ls21: 1 2 3 4
 lu21: 3 1 2 3 4 4 68 75 68 75 0 0 0 0 0 0 0 0 0 0 0 0 2b
+lu22: 3 1 2 3 4 4 68 75 68 75 0 0 0 0 0 0 0 0 0 0 0 0 2b
 lu3: 3 5 6 7 8 4 68 75 68 75 0 0 0 0 0 0 0 0 0 0 0 0 2b
 lu4: 3 5 6 7 0 5 62 6c 61 0 0 0 0 0 0 0 0 0 0 0 0 0 2c
 ls3: 1 2 3 4
 lv: 3 4 5 6 68 61 68 61 0 0 0 0 0 0 0 0 0 0 0 0 2d 2e
 lv2: 1 2 3 4 68 69 68 69 0 0 0 0 0 0 0 0 0 0 0 0 2f 30
 lv3: 7 8 9 a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 32
+flow: 9 8 7 6 0 0 0 0 0 0 0 0 0 0 0 0 6 5 4 3 0 0 0 0 0 0 0 0 0 0 0 0