Fix MSVC UNW_REMOTE_ONLY compilation errors

Fix errors observed while compiling libunwind for

  UNW_REMOTE_ONLY,
  library src,
  amd64 & aarch64 with an amd64 MSVC compile, and
  arm with an x86 MSVC compiler

Use standard compliant variadic macros

  GNUC offer non-compliant variadic macros
  Switch to standrds compiant variadic macros

Replace non-standard statement expression

   GNUC statement expression is non-ISO C compliant
   Where a simple inline function will be equivalent, use that instead

Gexpr.c support compilers w/o statement expressions

   For this case a simple inline function would change semantics
   Make a close approximation with a separate set of macros for non GNUC

Fix UNW_REMOTE_ONLY placement

  Exclude function call not required for remote only builds

Fix __attribute__((packed))

  On MSVC use pragma pack()

Add THREAD_LOCAL macro

  Avoid bare use of __thread

Add MSVC fetch_and_add() support

Use macro ALIGNED(x) in place of __attribute__((aligned(x))

Rename local ltoa to avoid name collision

  The Windows x86 SDK headers define ltoa.
  Rename this local function to avoid a name collision.

ISO C doesn't allow empty structures

  Add padding to allow empty arm/aarch64 structures to compile on MSVC

15 files changed, 124 insertions, 24 deletions

diff --git a/include/compiler.h b/include/compiler.h
index 2fa59eff..3100be09 100644
--- a/include/compiler.h
+++ b/include/compiler.h
@@ -30,6 +30,15 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
 #ifndef COMPILER_H
 #define COMPILER_H
 
+#if defined(__STDC_VERSION__ ) && __STDC_VERSION__  >= 201112L // C11
+# include <thread.h>
+# define THREAD_LOCAL thread_local
+#elseif defined(__GNUC__)
+# define THREAD_LOCAL __thread
+#else
+# define THREAD_LOCAL
+#endif
+
 #ifdef __GNUC__
 # define ALIGNED(x)     __attribute__((aligned(x)))
 # define CONST_ATTR     __attribute__((__const__))
@@ -67,6 +76,13 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
 # define unlikely(x)    (x)
 #endif
 
+#ifdef _MSC_VER
+#include <inttypes.h>
+uint32_t fetch_and_add(uint32_t* ptr, uint32_t value);
+# define fetch_and_add1(_ptr)           fetch_and_add(_ptr, 1)
+# define HAVE_FETCH_AND_ADD
+#endif
+
 #define ARRAY_SIZE(a)   (sizeof (a) / sizeof ((a)[0]))
 
 #endif /* COMPILER_H */
diff --git a/include/dwarf-eh.h b/include/dwarf-eh.h
index 96002a1b..f48e9190 100644
--- a/include/dwarf-eh.h
+++ b/include/dwarf-eh.h
@@ -107,6 +107,11 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
 
 #define DW_EH_VERSION           1       /* The version we're implementing */
 
+#ifdef _MSC_VER
+#pragma pack(push, 1)
+#define __attribute__(x)
+#endif
+
 struct __attribute__((packed)) dwarf_eh_frame_hdr
   {
     unsigned char version;
@@ -126,4 +131,9 @@ struct __attribute__((packed)) dwarf_eh_frame_hdr
         binary_search_table[fde_count];  */
   };
 
+#ifdef _MSC_VER
+#pragma pack(pop)
+#undef __attribute__
+#endif
+
 #endif /* dwarf_eh_h */
diff --git a/include/libunwind-aarch64.h b/include/libunwind-aarch64.h
index 2716afcc..2463d00c 100644
--- a/include/libunwind-aarch64.h
+++ b/include/libunwind-aarch64.h
@@ -34,6 +34,11 @@ extern "C" {
 #include <inttypes.h>
 #include <stddef.h>
 #include <ucontext.h>
+#include "compiler.h"
+
+#ifndef UNW_EMPTY_STRUCT
+# define UNW_EMPTY_STRUCT
+#endif
 
 #define UNW_TARGET      aarch64
 #define UNW_TARGET_AARCH64      1
@@ -60,6 +65,7 @@ typedef long double unw_tdep_fpreg_t;
 typedef struct
   {
     /* no aarch64-specific auxiliary proc-info */
+    UNW_EMPTY_STRUCT
   }
 unw_tdep_proc_info_t;
 
@@ -169,10 +175,10 @@ aarch64_regnum_t;
 typedef struct unw_tdep_save_loc
   {
     /* Additional target-dependent info on a save location.  */
+    UNW_EMPTY_STRUCT
   }
 unw_tdep_save_loc_t;
 
-
 /* On AArch64, we can directly use ucontext_t as the unwind context,
  * however, the __reserved struct is quite large: tune it down to only
  * the necessary used fields.  */
@@ -184,7 +190,7 @@ struct unw_sigcontext
 	uint64_t sp;
 	uint64_t pc;
 	uint64_t pstate;
-	uint8_t __reserved[(66 * 8)] __attribute__((__aligned__(16)));
+	uint8_t __reserved[(66 * 8)] ALIGNED(16);
 };
 
 typedef struct
diff --git a/include/libunwind-arm.h b/include/libunwind-arm.h
index 6709b7ab..ea14577b 100644
--- a/include/libunwind-arm.h
+++ b/include/libunwind-arm.h
@@ -32,6 +32,10 @@ extern "C" {
 #include <inttypes.h>
 #include <stddef.h>
 
+#ifndef UNW_EMPTY_STRUCT
+# define UNW_EMPTY_STRUCT
+#endif
+
 #define UNW_TARGET      arm
 #define UNW_TARGET_ARM  1
 
@@ -247,6 +251,7 @@ arm_regnum_t;
 typedef struct unw_tdep_save_loc
   {
     /* Additional target-dependent info on a save location.  */
+    UNW_EMPTY_STRUCT
   }
 unw_tdep_save_loc_t;
 
@@ -288,6 +293,7 @@ unw_tdep_context_t;
 typedef struct
   {
     /* no arm-specific auxiliary proc-info */
+    UNW_EMPTY_STRUCT
   }
 unw_tdep_proc_info_t;
 
diff --git a/include/libunwind_i.h b/include/libunwind_i.h
index e0f45401..3eecab72 100644
--- a/include/libunwind_i.h
+++ b/include/libunwind_i.h
@@ -275,7 +275,7 @@ extern pthread_mutex_t _U_dyn_info_list_lock;
 extern long unwi_debug_level;
 
 # include <stdio.h>
-# define Debug(level,format...)                                         \
+# define Debug(level, /* format */ ...)                                 \
 do {                                                                    \
   if (unwi_debug_level >= level)                                        \
     {                                                                   \
@@ -283,13 +283,14 @@ do {                                                                    \
       if (_n > 16)                                                      \
         _n = 16;                                                        \
       fprintf (stderr, "%*c>%s: ", _n, ' ', __FUNCTION__);              \
-      fprintf (stderr, format);                                         \
+      fprintf (stderr, /* format */ __VA_ARGS__);                       \
     }                                                                   \
 } while (0)
-# define Dprintf(format...)         fprintf (stderr, format)
+# define Dprintf(/* format */ ...)                                      \
+  fprintf (stderr, /* format */ __VA_ARGS__)
 #else
-# define Debug(level,format...)
-# define Dprintf(format...)
+# define Debug(level, /* format */ ...)
+# define Dprintf( /* format */ ...)
 #endif
 
 static ALWAYS_INLINE int
diff --git a/include/tdep-aarch64/libunwind_i.h b/include/tdep-aarch64/libunwind_i.h
index b91273fa..6996b98b 100644
--- a/include/tdep-aarch64/libunwind_i.h
+++ b/include/tdep-aarch64/libunwind_i.h
@@ -160,8 +160,14 @@ dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
 # define DWARF_LOC_TYPE_FP      (1 << 0)
 # define DWARF_LOC_TYPE_REG     (1 << 1)
 # define DWARF_NULL_LOC         DWARF_LOC (0, 0)
-# define DWARF_IS_NULL_LOC(l)                                           \
-                ({ dwarf_loc_t _l = (l); _l.val == 0 && _l.type == 0; })
+
+static inline int
+dwarf_is_null_loc(dwarf_loc_t l)
+{
+  return l.val == 0 && l.type == 0;
+}
+
+# define DWARF_IS_NULL_LOC(l)   dwarf_is_null_loc(l)
 # define DWARF_LOC(r, t)        ((dwarf_loc_t) { .val = (r), .type = (t) })
 # define DWARF_IS_REG_LOC(l)    (((l).type & DWARF_LOC_TYPE_REG) != 0)
 # define DWARF_IS_FP_LOC(l)     (((l).type & DWARF_LOC_TYPE_FP) != 0)
diff --git a/include/tdep-arm/libunwind_i.h b/include/tdep-arm/libunwind_i.h
index 2602f41c..19ae4c30 100644
--- a/include/tdep-arm/libunwind_i.h
+++ b/include/tdep-arm/libunwind_i.h
@@ -151,8 +151,14 @@ dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
 # define DWARF_LOC_TYPE_FP      (1 << 0)
 # define DWARF_LOC_TYPE_REG     (1 << 1)
 # define DWARF_NULL_LOC         DWARF_LOC (0, 0)
-# define DWARF_IS_NULL_LOC(l)                                           \
-                ({ dwarf_loc_t _l = (l); _l.val == 0 && _l.type == 0; })
+
+static inline int
+dwarf_is_null_loc(dwarf_loc_t l)
+{
+  return l.val == 0 && l.type == 0;
+}
+
+# define DWARF_IS_NULL_LOC(l)   dwarf_is_null_loc(l)
 # define DWARF_LOC(r, t)        ((dwarf_loc_t) { .val = (r), .type = (t) })
 # define DWARF_IS_REG_LOC(l)    (((l).type & DWARF_LOC_TYPE_REG) != 0)
 # define DWARF_IS_FP_LOC(l)     (((l).type & DWARF_LOC_TYPE_FP) != 0)
diff --git a/include/tdep-x86_64/libunwind_i.h b/include/tdep-x86_64/libunwind_i.h
index 6b798c71..ddfd7da1 100644
--- a/include/tdep-x86_64/libunwind_i.h
+++ b/include/tdep-x86_64/libunwind_i.h
@@ -130,8 +130,14 @@ dwarf_get_uc(const struct dwarf_cursor *cursor)
 #else /* !UNW_LOCAL_ONLY */
 
 # define DWARF_NULL_LOC         DWARF_LOC (0, 0)
-# define DWARF_IS_NULL_LOC(l)                                           \
-                ({ dwarf_loc_t _l = (l); _l.val == 0 && _l.type == 0; })
+
+static inline int
+dwarf_is_null_loc(dwarf_loc_t l)
+{
+  return l.val == 0 && l.type == 0;
+}
+
+# define DWARF_IS_NULL_LOC(l)   dwarf_is_null_loc(l)
 # define DWARF_REG_LOC(c,r)     DWARF_LOC((r), DWARF_LOC_TYPE_REG)
 # define DWARF_FPREG_LOC(c,r)   DWARF_LOC((r), (DWARF_LOC_TYPE_REG      \
                                                 | DWARF_LOC_TYPE_FP))
diff --git a/src/aarch64/Gtrace.c b/src/aarch64/Gtrace.c
index c67faf0e..2f8c3f8d 100644
--- a/src/aarch64/Gtrace.c
+++ b/src/aarch64/Gtrace.c
@@ -52,8 +52,8 @@ static pthread_once_t trace_cache_once = PTHREAD_ONCE_INIT;
 static sig_atomic_t trace_cache_once_happen;
 static pthread_key_t trace_cache_key;
 static struct mempool trace_cache_pool;
-static __thread  unw_trace_cache_t *tls_cache;
-static __thread  int tls_cache_destroyed;
+static THREAD_LOCAL  unw_trace_cache_t *tls_cache;
+static THREAD_LOCAL  int tls_cache_destroyed;
 
 /* Free memory for a thread's trace cache. */
 static void
diff --git a/src/arm/Gtrace.c b/src/arm/Gtrace.c
index 2f277520..7ed320cc 100644
--- a/src/arm/Gtrace.c
+++ b/src/arm/Gtrace.c
@@ -52,8 +52,8 @@ static pthread_once_t trace_cache_once = PTHREAD_ONCE_INIT;
 static sig_atomic_t trace_cache_once_happen;
 static pthread_key_t trace_cache_key;
 static struct mempool trace_cache_pool;
-static __thread  unw_trace_cache_t *tls_cache;
-static __thread  int tls_cache_destroyed;
+static THREAD_LOCAL  unw_trace_cache_t *tls_cache;
+static THREAD_LOCAL  int tls_cache_destroyed;
 
 /* Free memory for a thread's trace cache. */
 static void
diff --git a/src/dwarf/Gexpr.c b/src/dwarf/Gexpr.c
index 2af45433..830fd14c 100644
--- a/src/dwarf/Gexpr.c
+++ b/src/dwarf/Gexpr.c
@@ -251,6 +251,7 @@ dwarf_eval_expr (struct dwarf_cursor *c, unw_word_t stack_val, unw_word_t *addr,
   uint32_t u32;
   uint64_t u64;
   int ret;
+#ifdef __GNUC__
 # define pop()                                  \
 ({                                              \
   if ((tos - 1) >= MAX_EXPR_STACK_SIZE)         \
@@ -280,6 +281,48 @@ do {                                            \
     }                                           \
   stack[_index];                                \
 })
+#else // __GNUC__
+// We don't have non-standard statement expressions
+// Use multiple statements instead
+int stackerror = 0;
+
+// pop() is either followed by a semicolon or
+// used in a push() macro
+// In either case we can sneak in an extra statement
+# define pop()                                  \
+(((tos - 1) >= MAX_EXPR_STACK_SIZE) ?           \
+  stackerror++ :   stack[--tos]);               \
+if (stackerror)                                 \
+  {                                             \
+    Debug (1, "Stack underflow\n");             \
+    return -UNW_EINVAL;                         \
+  }
+
+// Removed the parentheses on the asignment
+// to allow the extra stack error check
+// when x is evaluated
+# define push(x)                                \
+do {                                            \
+  unw_word_t _x = x;                            \
+  if (tos >= MAX_EXPR_STACK_SIZE)               \
+    {                                           \
+      Debug (1, "Stack overflow\n");            \
+      return -UNW_EINVAL;                       \
+    }                                           \
+  stack[tos++] = _x;                            \
+} while (0)
+
+// Pick is always used in a push() macro
+// In either case we can sneak in an extra statement
+# define pick(n)                                \
+(((tos - 1 - (n)) >= MAX_EXPR_STACK_SIZE) ?     \
+  stackerror++ : stack[tos - 1 - (n)]);         \
+if (stackerror)                                 \
+  {                                             \
+    Debug (1, "Out-of-stack pick\n");           \
+    return -UNW_EINVAL;                         \
+  }
+#endif // __GNUC__
 
   as = c->as;
   arg = c->as_arg;
diff --git a/src/os-linux.h b/src/os-linux.h
index 3976b38c..5a9b0b40 100644
--- a/src/os-linux.h
+++ b/src/os-linux.h
@@ -38,7 +38,7 @@ struct map_iterator
   };
 
 static inline char *
-ltoa (char *buf, long val)
+unw_ltoa (char *buf, long val)
 {
   char *cp = buf, tmp;
   ssize_t i, len;
@@ -68,7 +68,7 @@ maps_init (struct map_iterator *mi, pid_t pid)
   char path[sizeof ("/proc/0123456789/maps")], *cp;
 
   memcpy (path, "/proc/", 6);
-  cp = ltoa (path + 6, pid);
+  cp = unw_ltoa (path + 6, pid);
   assert (cp + 6 < path + sizeof (path));
   memcpy (cp, "/maps", 6);
 
diff --git a/src/x86_64/Gglobal.c b/src/x86_64/Gglobal.c
index 9a7b1957..73ba02e3 100644
--- a/src/x86_64/Gglobal.c
+++ b/src/x86_64/Gglobal.c
@@ -96,9 +96,9 @@ tdep_init (void)
 
     dwarf_init ();
 
+#ifndef UNW_REMOTE_ONLY
     tdep_init_mem_validate ();
 
-#ifndef UNW_REMOTE_ONLY
     x86_64_local_addr_space_init ();
 #endif
     fetch_and_add1(&tdep_init_done); /* signal that we're initialized... */
diff --git a/src/x86_64/Ginit.c b/src/x86_64/Ginit.c
index fd8d418b..81c663c1 100644
--- a/src/x86_64/Ginit.c
+++ b/src/x86_64/Ginit.c
@@ -205,8 +205,8 @@ tdep_init_mem_validate (void)
 #define NLGA 4
 #if defined(HAVE___THREAD) && HAVE___THREAD
 // thread-local variant
-static __thread unw_word_t last_good_addr[NLGA];
-static __thread int lga_victim;
+static THREAD_LOCAL unw_word_t last_good_addr[NLGA];
+static THREAD_LOCAL int lga_victim;
 
 static int
 is_cached_valid_mem(unw_word_t addr)
diff --git a/src/x86_64/Gtrace.c b/src/x86_64/Gtrace.c
index 824527f9..7be10a00 100644
--- a/src/x86_64/Gtrace.c
+++ b/src/x86_64/Gtrace.c
@@ -50,8 +50,8 @@ static pthread_once_t trace_cache_once = PTHREAD_ONCE_INIT;
 static sig_atomic_t trace_cache_once_happen;
 static pthread_key_t trace_cache_key;
 static struct mempool trace_cache_pool;
-static __thread  unw_trace_cache_t *tls_cache;
-static __thread  int tls_cache_destroyed;
+static THREAD_LOCAL  unw_trace_cache_t *tls_cache;
+static THREAD_LOCAL  int tls_cache_destroyed;
 
 /* Free memory for a thread's trace cache. */
 static void