From b4755c5aa7ede517bf9bc559e9247c050c6711f2 Mon Sep 17 00:00:00 2001
From: liaogang <liaogang@baidu.com>
Date: Mon, 14 Aug 2017 15:50:28 +0800
Subject: [PATCH 1/3] Demangle exception call stack for PADDLE_ENFORCE

---
 paddle/platform/enforce.h | 47 ++++++++++++++++++++++++++++++++-------
 1 file changed, 39 insertions(+), 8 deletions(-)

diff --git a/paddle/platform/enforce.h b/paddle/platform/enforce.h
index 337a059fb1494d..aa0660df88a057 100644
--- a/paddle/platform/enforce.h
+++ b/paddle/platform/enforce.h
@@ -14,14 +14,20 @@ limitations under the License. */
 
 #pragma once
 
-#include <execinfo.h>
+#include <dlfcn.h>     // for dladdr
+#include <execinfo.h>  // for backtrace
 #include <iomanip>
 #include <sstream>
 #include <stdexcept>
 #include <string>
+
 #include "paddle/string/printf.h"
 #include "paddle/string/to_string.h"
 
+#ifdef __GNUC__
+#include <cxxabi.h>  // for __cxa_demangle
+#endif
+
 #ifndef PADDLE_ONLY_CPU
 
 #include "paddle/platform/dynload/cublas.h"
@@ -39,6 +45,19 @@ limitations under the License. */
 namespace paddle {
 namespace platform {
 
+namespace {
+#ifdef __GNUC__
+inline std::string demangle(std::string name) {
+  int status = -4;  // some arbitrary value to eliminate the compiler warning
+  std::unique_ptr<char, void (*)(void*)> res{
+      abi::__cxa_demangle(name.c_str(), NULL, NULL, &status), std::free};
+  return (status == 0) ? res.get() : name;
+}
+#else
+inline std::string demangle(std::string name) { return name; }
+#endif
+}
+
 struct EnforceNotMet : public std::exception {
   std::exception_ptr exp_;
   std::string err_str_;
@@ -48,15 +67,27 @@ struct EnforceNotMet : public std::exception {
       std::rethrow_exception(exp_);
     } catch (const std::exception& exp) {
       std::ostringstream sout;
+
       sout << string::Sprintf("%s at [%s:%d]", exp.what(), f, l) << std::endl;
-      sout << "Call Stacks: " << std::endl;
+      sout << "PaddlePaddle Call Stacks: " << std::endl;
+
       void* call_stack[TRACE_STACK_LIMIT];
-      int sz = backtrace(call_stack, TRACE_STACK_LIMIT);
-      auto line = backtrace_symbols(call_stack, sz);
-      for (int i = 0; i < sz; ++i) {
-        sout << line[i] << std::endl;
+      auto size = backtrace(call_stack, TRACE_STACK_LIMIT);
+      auto symbols = backtrace_symbols(call_stack, size);
+
+      Dl_info info;
+      for (int i = 0; i < size; ++i) {
+        if (dladdr(call_stack[i], &info)) {
+          auto demangled = demangle(info.dli_sname);
+          sout << string::Sprintf(
+              "%-3d %*0p %s + %zd\n", i, 2 + sizeof(void*) * 2, call_stack[i],
+              demangled, (char*)call_stack[i] - (char*)info.dli_saddr);
+        } else {
+          sout << string::Sprintf("%-3d %*0p %s\n", i, 2 + sizeof(void*) * 2,
+                                  call_stack[i]);
+        }
       }
-      free(line);
+      free(symbols);
       err_str_ = sout.str();
     }
   }
@@ -170,7 +201,7 @@ inline void throw_on_error(T e) {
  *    PADDLE_ENFORCE_EQ(a, b);
  *
  *    will raise an expression described as follows:
- *    "enforce a == b failed, 1 != 2" with detailed stack infomation.
+ *    "enforce a == b failed, 1 != 2" with detailed stack information.
  *
  *    extra messages is also supported, for example:
  *    PADDLE_ENFORCE(a, b, "some simple enforce failed between %d numbers", 2)

From 8210bcea6116be008aa027c6e868acbf5ebfeda6 Mon Sep 17 00:00:00 2001
From: liaogang <liaogang@baidu.com>
Date: Mon, 14 Aug 2017 15:59:02 +0800
Subject: [PATCH 2/3] Using static_cast<char*> to replace (char*)

---
 paddle/platform/enforce.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/paddle/platform/enforce.h b/paddle/platform/enforce.h
index aa0660df88a057..cc38dc4ffede09 100644
--- a/paddle/platform/enforce.h
+++ b/paddle/platform/enforce.h
@@ -79,9 +79,11 @@ struct EnforceNotMet : public std::exception {
       for (int i = 0; i < size; ++i) {
         if (dladdr(call_stack[i], &info)) {
           auto demangled = demangle(info.dli_sname);
-          sout << string::Sprintf(
-              "%-3d %*0p %s + %zd\n", i, 2 + sizeof(void*) * 2, call_stack[i],
-              demangled, (char*)call_stack[i] - (char*)info.dli_saddr);
+          auto addr_offset = static_cast<char*>(call_stack[i]) -
+                             static_cast<char*>(info.dli_saddr);
+          sout << string::Sprintf("%-3d %*0p %s + %zd\n", i,
+                                  2 + sizeof(void*) * 2, call_stack[i],
+                                  demangled, addr_offset);
         } else {
           sout << string::Sprintf("%-3d %*0p %s\n", i, 2 + sizeof(void*) * 2,
                                   call_stack[i]);

From ffbb4c19634778d5380954dd55f4f56ec17b3859 Mon Sep 17 00:00:00 2001
From: liaogang <liaogang@baidu.com>
Date: Mon, 14 Aug 2017 16:27:25 +0800
Subject: [PATCH 3/3] memory.h for unique_ptr

---
 paddle/platform/enforce.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/paddle/platform/enforce.h b/paddle/platform/enforce.h
index cc38dc4ffede09..15fdf7a94f462a 100644
--- a/paddle/platform/enforce.h
+++ b/paddle/platform/enforce.h
@@ -17,6 +17,7 @@ limitations under the License. */
 #include <dlfcn.h>     // for dladdr
 #include <execinfo.h>  // for backtrace
 #include <iomanip>
+#include <memory>
 #include <sstream>
 #include <stdexcept>
 #include <string>