From e8b3503cf48f225569697a7603ad8769ef8942ac Mon Sep 17 00:00:00 2001
From: k-hara <k.hara.pg@gmail.com>
Date: Tue, 24 Dec 2013 13:12:14 +0900
Subject: [PATCH] fix Issue 11767 - doubly mixed-in struct "failed semantic
 analysis"

Inherently this is a mangling issue, which had been hidden since 2a3db5d7afd0c26e8a0ec58ff6fb6a8cd9647de6, and then detected by [the assertion for AST sanity](20fe5e8600498fed322a7d5d8305acb2de852cde).

Each mixed-in symbols are in independent scope, and their mangled names should also be different.
To fix the issue, assign scope-local unique name for each unnamed `TemplateMixin`s, as same as lambdas.
---
 src/template.c         | 28 ++++++++++++++++++++++++++--
 test/runnable/mixin1.d | 27 +++++++++++++++++++++++++++
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/src/template.c b/src/template.c
index 0cf2b4991c7f..529b2e806c13 100644
--- a/src/template.c
+++ b/src/template.c
@@ -7491,7 +7491,31 @@ void TemplateMixin::semantic(Scope *sc)
     assert(tempdecl);
 
     if (!ident)
-        ident = genIdent(tiargs);
+    {
+        /* Assign scope local unique identifier, as same as lambdas.
+         */
+        const char *s = "__mixin";
+
+        DsymbolTable *symtab;
+        if (FuncDeclaration *func = sc->parent->isFuncDeclaration())
+        {
+            symtab = func->localsymtab;
+            if (symtab)
+            {
+                // Inside template constraint, symtab is not set yet.
+                goto L1;
+            }
+        }
+        else
+        {
+            symtab = sc->parent->isScopeDsymbol()->symtab;
+        L1:
+            assert(symtab);
+            int num = (int)_aaLen(symtab->tab) + 1;
+            ident = Lexer::uniqueId(s, num);
+            symtab->insert(this);
+        }
+    }
 
     inst = this;
     parent = sc->parent;
@@ -7815,7 +7839,7 @@ void TemplateMixin::toCBuffer(OutBuffer *buf, HdrGenState *hgs)
     tqual->toCBuffer(buf, NULL, hgs);
     toCBufferTiargs(buf, hgs);
 
-    if (ident)
+    if (ident && memcmp(ident->string, "__mixin", 7) != 0)
     {
         buf->writebyte(' ');
         buf->writestring(ident->toChars());
diff --git a/test/runnable/mixin1.d b/test/runnable/mixin1.d
index e1f04439858e..4c24c8368290 100644
--- a/test/runnable/mixin1.d
+++ b/test/runnable/mixin1.d
@@ -1233,6 +1233,32 @@ class C11487
     mixin M.Mix!(M.R);
 }
 
+/*******************************************/
+// 11767
+
+mixin template M11767()
+{
+    struct S11767 {}
+}
+mixin M11767!();
+mixin M11767!();    // OK
+static assert(!__traits(compiles, S11767));
+
+void test11767()
+{
+    mixin M11767!();
+    alias S1 = S11767;
+    {
+        mixin M11767!();
+        alias S2 = S11767;
+        static assert(!is(S1 == S2));
+        static assert(S1.mangleof == "S6mixin19test11767FZv8__mixin16S11767");
+        static assert(S2.mangleof == "S6mixin19test11767FZv8__mixin26S11767");
+    }
+    mixin M11767!();
+    static assert(!__traits(compiles, S11767));
+}
+
 /*******************************************/
 
 int main()
@@ -1282,6 +1308,7 @@ int main()
     test2740();
     test42();
     test9417();
+    test11767();
 
     printf("Success\n");
     return 0;