From 96c16b742b9f0c2ebe22cc48c10b4cf2f08429d4 Mon Sep 17 00:00:00 2001
From: Alexey Milovidov <milovidov@yandex-team.ru>
Date: Fri, 6 Feb 2015 09:49:37 +0300
Subject: [PATCH] Separated test case for compiler bug [#METR-10240].

---
 dbms/src/IO/tests/io_and_exceptions.cpp | 145 ++++++++++++++++++++++--
 1 file changed, 137 insertions(+), 8 deletions(-)

diff --git a/dbms/src/IO/tests/io_and_exceptions.cpp b/dbms/src/IO/tests/io_and_exceptions.cpp
index 77127cb278d..e832707e5a1 100644
--- a/dbms/src/IO/tests/io_and_exceptions.cpp
+++ b/dbms/src/IO/tests/io_and_exceptions.cpp
@@ -1,13 +1,143 @@
-#include <DB/IO/ReadBufferFromFile.h>
-#include <DB/IO/CompressedReadBuffer.h>
-#include <DB/IO/ReadHelpers.h>
+/** Воспроизводит баг в gcc 4.8.2
+  * Баг: исключение не ловится.
+  *
+  * /usr/bin/c++ -std=c++11 -Wall -O3 ./io_and_exceptions.cpp && ./a.out
+  *
+  * Выводит:
+  * terminate called after throwing an instance of 'int'
+  * Aborted
+  *
+  * А должно ничего не выводить.
+  *
+  * В gcc 4.9 и clang 3.6 всё Ок.
+  */
+
+typedef unsigned long size_t;
+
+class BufferBase
+{
+public:
+	typedef char * Position;
+
+	struct Buffer
+	{
+		Buffer(Position begin_pos_, Position end_pos_) : begin_pos(begin_pos_), end_pos(end_pos_) {}
+
+		inline Position begin() const { return begin_pos; }
+		inline Position end() const { return end_pos; }
+		inline size_t size() const { return end_pos - begin_pos; }
+		inline void resize(size_t size) { end_pos = begin_pos + size; }
+
+	private:
+		Position begin_pos;
+		Position end_pos;
+	};
+
+	BufferBase(Position ptr, size_t size, size_t offset)
+		: internal_buffer(ptr, ptr + size), working_buffer(ptr, ptr + size), pos(ptr + offset),	bytes(0) {}
+
+	void set(Position ptr, size_t size, size_t offset)
+	{
+		internal_buffer = Buffer(ptr, ptr + size);
+		working_buffer = Buffer(ptr, ptr + size);
+		pos = ptr + offset;
+	}
+
+	inline Buffer & buffer() { return working_buffer; }
+	inline Position & position() { return pos; };
+	inline size_t offset() const { return pos - working_buffer.begin(); }
+
+	size_t count() const
+	{
+		return bytes + offset();
+	}
+
+protected:
+	Buffer internal_buffer;
+	Buffer working_buffer;
+
+	Position pos;
+	size_t bytes;
+};
+
+
+class ReadBuffer : public BufferBase
+{
+public:
+	ReadBuffer(Position ptr, size_t size) : BufferBase(ptr, size, 0) { working_buffer.resize(0); }
+	ReadBuffer(Position ptr, size_t size, size_t offset) : BufferBase(ptr, size, offset) {}
+
+	inline bool next()
+	{
+		bytes += offset();
+		bool res = nextImpl();
+		if (!res)
+			working_buffer.resize(0);
+
+		pos = working_buffer.begin();
+		return res;
+	}
+
+	virtual ~ReadBuffer() {}
+
+	inline bool eof()
+	{
+		return pos == working_buffer.end() && !next();
+	}
+
+private:
+	virtual bool nextImpl() { return false; };
+};
+
+
+class CompressedReadBuffer : public ReadBuffer
+{
+private:
+	bool nextImpl()
+	{
+		throw 1;
+		return true;
+	}
+
+public:
+	CompressedReadBuffer() : ReadBuffer(nullptr, 0)
+	{
+	}
+};
+
+
+void readIntText(unsigned & x, ReadBuffer & buf)
+{
+	x = 0;
+	while (!buf.eof())
+	{
+		switch (*buf.position())
+		{
+			case '+':
+				break;
+			case '9':
+				x *= 10;
+				break;
+			default:
+				return;
+		}
+	}
+}
+
+
+unsigned parse(const char * data)
+{
+	unsigned res;
+	ReadBuffer buf(const_cast<char *>(data), 10, 0);
+	readIntText(res, buf);
+	return res;
+}
+
 
 
 int main()
 {
-	const char * s = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
-	DB::ReadBuffer file_in(const_cast<char *>(s), 32, 0);
-	DB::CompressedReadBuffer in(file_in);
+	CompressedReadBuffer in;
 
 	try
 	{
@@ -16,7 +146,6 @@ int main()
 	}
 	catch (...)
 	{
-		std::cerr << "Catched!\n";
 	}
 
 	return 0;
@@ -25,5 +154,5 @@ int main()
 
 void f()
 {
-	DB::parse<UInt64>("123");
+	parse("123");
 }