prevent name mangling for C++ DLLs

compiler/ccgutils.nim

@@ -9,31 +9,31 @@
 
 # This module declares some helpers for the C code generator.
 
-import 
-  ast, astalgo, ropes, lists, hashes, strutils, types, msgs, wordrecg, 
+import
+  ast, astalgo, ropes, lists, hashes, strutils, types, msgs, wordrecg,
   platform, trees
 
 proc getPragmaStmt*(n: PNode, w: TSpecialWord): PNode =
   case n.kind
-  of nkStmtList: 
-    for i in 0 .. < n.len: 
+  of nkStmtList:
+    for i in 0 .. < n.len:
       result = getPragmaStmt(n[i], w)
       if result != nil: break
   of nkPragma:
-    for i in 0 .. < n.len: 
+    for i in 0 .. < n.len:
       if whichPragma(n[i]) == w: return n[i]
   else: discard
 
 proc stmtsContainPragma*(n: PNode, w: TSpecialWord): bool =
   result = getPragmaStmt(n, w) != nil
 
-proc hashString*(s: string): BiggestInt = 
+proc hashString*(s: string): BiggestInt =
   # has to be the same algorithm as system.hashString!
-  if CPU[targetCPU].bit == 64: 
+  if CPU[targetCPU].bit == 64:
     # we have to use the same bitwidth
     # as the target CPU
     var b = 0'i64
-    for i in countup(0, len(s) - 1): 
+    for i in countup(0, len(s) - 1):
       b = b +% ord(s[i])
       b = b +% `shl`(b, 10)
       b = b xor `shr`(b, 6)
@@ -41,9 +41,9 @@ proc hashString*(s: string): BiggestInt =
     b = b xor `shr`(b, 11)
     b = b +% `shl`(b, 15)
     result = b
-  else: 
+  else:
     var a = 0'i32
-    for i in countup(0, len(s) - 1): 
+    for i in countup(0, len(s) - 1):
       a = a +% ord(s[i]).int32
       a = a +% `shl`(a, 10'i32)
       a = a xor `shr`(a, 6'i32)
@@ -52,11 +52,11 @@ proc hashString*(s: string): BiggestInt =
     a = a +% `shl`(a, 15'i32)
     result = a
 
-var 
+var
   gTypeTable: array[TTypeKind, TIdTable]
   gCanonicalTypes: array[TTypeKind, PType]
 
-proc initTypeTables() = 
+proc initTypeTables() =
   for i in countup(low(TTypeKind), high(TTypeKind)): initIdTable(gTypeTable[i])
 
 proc resetCaches* =
@@ -67,7 +67,7 @@ proc resetCaches* =
 
 when false:
   proc echoStats*() =
-    for i in countup(low(TTypeKind), high(TTypeKind)): 
+    for i in countup(low(TTypeKind), high(TTypeKind)):
       echo i, " ", gTypeTable[i].counter
 
 proc slowSearch(key: PType; k: TTypeKind): PType =
@@ -78,21 +78,21 @@ proc slowSearch(key: PType; k: TTypeKind): PType =
   if idTableHasObjectAsKey(gTypeTable[k], key): return key
   for h in countup(0, high(gTypeTable[k].data)):
     var t = PType(gTypeTable[k].data[h].key)
-    if t != nil and sameBackendType(t, key): 
+    if t != nil and sameBackendType(t, key):
       return t
   idTablePut(gTypeTable[k], key, key)
   result = key
 
-proc getUniqueType*(key: PType): PType = 
+proc getUniqueType*(key: PType): PType =
   # this is a hotspot in the compiler!
-  if key == nil: return 
+  if key == nil: return
   var k = key.kind
   case k
   of tyBool, tyChar, tyInt..tyUInt64:
     # no canonicalization for integral types, so that e.g. ``pid_t`` is
     # produced instead of ``NI``.
     result = key
-  of  tyEmpty, tyNil, tyExpr, tyStmt, tyPointer, tyString, 
+  of  tyEmpty, tyNil, tyExpr, tyStmt, tyPointer, tyString,
       tyCString, tyNone, tyBigNum:
     result = gCanonicalTypes[k]
     if result == nil:
@@ -127,7 +127,7 @@ proc getUniqueType*(key: PType): PType =
     if tfFromGeneric notin key.flags:
       # fast case; lookup per id suffices:
       result = PType(idTableGet(gTypeTable[k], key))
-      if result == nil: 
+      if result == nil:
         idTablePut(gTypeTable[k], key, key)
         result = key
     else:
@@ -138,10 +138,10 @@ proc getUniqueType*(key: PType): PType =
         if t != nil and sameBackendType(t, key):
           return t
       idTablePut(gTypeTable[k], key, key)
-      result = key    
+      result = key
   of tyEnum:
     result = PType(idTableGet(gTypeTable[k], key))
-    if result == nil: 
+    if result == nil:
       idTablePut(gTypeTable[k], key, key)
       result = key
   of tyProc:
@@ -151,16 +151,16 @@ proc getUniqueType*(key: PType): PType =
       # ugh, we need the canon here:
       result = slowSearch(key, k)
 
-proc tableGetType*(tab: TIdTable, key: PType): RootRef = 
+proc tableGetType*(tab: TIdTable, key: PType): RootRef =
   # returns nil if we need to declare this type
   result = idTableGet(tab, key)
-  if (result == nil) and (tab.counter > 0): 
+  if (result == nil) and (tab.counter > 0):
     # we have to do a slow linear search because types may need
     # to be compared by their structure:
-    for h in countup(0, high(tab.data)): 
+    for h in countup(0, high(tab.data)):
       var t = PType(tab.data[h].key)
-      if t != nil: 
-        if sameType(t, key): 
+      if t != nil:
+        if sameType(t, key):
           return tab.data[h].val
 
 proc makeSingleLineCString*(s: string): string =
@@ -193,16 +193,16 @@ proc mangle*(name: string): string =
     else:
       add(result, "HEX" & toHex(ord(c), 2))
 
-proc makeLLVMString*(s: string): PRope = 
+proc makeLLVMString*(s: string): PRope =
   const MaxLineLength = 64
   result = nil
   var res = "c\""
-  for i in countup(0, len(s) - 1): 
-    if (i + 1) mod MaxLineLength == 0: 
+  for i in countup(0, len(s) - 1):
+    if (i + 1) mod MaxLineLength == 0:
       app(result, toRope(res))
       setLen(res, 0)
     case s[i]
-    of '\0'..'\x1F', '\x80'..'\xFF', '\"', '\\': 
+    of '\0'..'\x1F', '\x80'..'\xFF', '\"', '\\':
       add(res, '\\')
       add(res, toHex(ord(s[i]), 2))
     else: add(res, s[i])

lib/nimbase.h

@@ -67,7 +67,7 @@ __clang__
 #endif
 
 #if (defined(WIN32) || defined(_WIN32) || defined(__WIN32__))
-#  define NIM_THREADVAR __declspec(thread) 
+#  define NIM_THREADVAR __declspec(thread)
 #else
 #  define NIM_THREADVAR __thread
 #endif
@@ -103,7 +103,11 @@ __clang__
 #  define N_FASTCALL_PTR(rettype, name) rettype (__fastcall *name)
 #  define N_SAFECALL_PTR(rettype, name) rettype (__safecall *name)
 
-#  define N_LIB_EXPORT  extern __declspec(dllexport)
+#  ifdef __cplusplus
+#    define N_LIB_EXPORT  extern "C" __declspec(dllexport)
+#  else
+#    define N_LIB_EXPORT  extern __declspec(dllexport)
+#  endif
 #  define N_LIB_IMPORT  extern __declspec(dllimport)
 #else
 #  define N_CDECL(rettype, name) rettype name
@@ -118,7 +122,11 @@ __clang__
 #  define N_FASTCALL_PTR(rettype, name) rettype (*name)
 #  define N_SAFECALL_PTR(rettype, name) rettype (*name)
 
-#  define N_LIB_EXPORT  extern
+#  ifdef __cplusplus
+#    define N_LIB_EXPORT  extern "C"
+#  else
+#    define N_LIB_EXPORT  extern
+#  endif
 #  define N_LIB_IMPORT  extern
 #endif
 
@@ -345,7 +353,7 @@ struct TFrame {
 #define nimln(n, file) \
   F.line = n; F.filename = file;
 
-#define NIM_POSIX_INIT  __attribute__((constructor)) 
+#define NIM_POSIX_INIT  __attribute__((constructor))
 
 #if defined(_MSCVER) && defined(__i386__)
 __declspec(naked) int __fastcall NimXadd(volatile int* pNum, int val) {
@@ -380,7 +388,7 @@ static inline void GCGuard (void *ptr) { asm volatile ("" :: "X" (ptr)); }
 #endif
 
 /* Test to see if Nim and the C compiler agree on the size of a pointer.
-   On disagreement, your C compiler will say something like: 
+   On disagreement, your C compiler will say something like:
    "error: 'assert_numbits' declared as an array with a negative size" */
 typedef int assert_numbits[sizeof(NI) == sizeof(void*) && NIM_INTBITS == sizeof(NI)*8 ? 1 : -1];
 #endif