Binary compatibility report for the Clipper library between 6.1.3 and 6.2.0 versions on x86

Test Info

Library Name	Clipper
Version #1	6.1.3
Version #2	6.2.0
CPU Type	x86
GCC Version	4.6.1

Test Results

Total Header Files	1
Total Shared Libraries	1
Total Symbols / Types	66 / 59
Verdict	Incompatible (69.7%)

Problem Summary

	Severity	Count
Added Symbols	-	2
Removed Symbols	High	3
Problems with Data Types	High	5
	Medium	2
	Low	4
Problems with Symbols	High	1
	Medium	0
	Low	0
Problems with Constants	Low	0
Other Changes in Data Types	-	1

Added Symbols (2)

clipper.hpp, libpolyclipping.so.18.0.0
namespace ClipperLib
MinkowskiSum ( Path const& pattern, Paths const& paths, Paths& solution, bool pathIsClosed )
PolyNode::~PolyNode [in-charge-deleting] ( )

to the top

Removed Symbols (3)

clipper.hpp, libpolyclipping.so.16.0.0
namespace ClipperLib
ClipperBase::InsertLocalMinima ( struct LocalMinima* newLm )
MinkowskiSum ( Path const& pattern, Paths const& paths, Paths& solution, enum PolyFillType pathFillType, bool pathIsClosed )
OffsetPaths ( Paths const& in_polys, Paths& out_polys, double delta, enum JoinType jointype, enum EndType_ endtype, double limit )

to the top

Problems with Data Types, High Severity (5)

	Change	Effect
1	Size of this class has been increased from 32 bytes to 40 bytes.	1) An object of this class can be allocated by the applications and old size will be hardcoded at the compile time. Call of any exported constructor will break the memory of neighboring objects on the stack or heap. 2) The memory layout and size of subclasses will be changed.

	Change	Effect
1	Size of this class has been increased from 172 bytes to 176 bytes.	1) An object of this class can be allocated by the applications and old size will be hardcoded at the compile time. Call of any exported constructor will break the memory of neighboring objects on the stack or heap. 2) The memory layout and size of subclasses will be changed.

	Change	Effect
1	Size of this class has been increased from 44 bytes to 48 bytes.	1) An object of this class can be allocated by the applications and old size will be hardcoded at the compile time. Call of any exported constructor will break the memory of neighboring objects on the stack or heap. 2) The memory layout and size of subclasses will be changed.
2	First virtual method PolyNode::~PolyNode ( ) has been added to this class.	1) The layout of type structure has been shifted by 4 bytes by the added v-table pointer. 2) Size of class has been increased by 4 bytes.

	Change	Effect
1	Size of this class has been changed from 56 bytes to 60 bytes.	1) The class has only inline or auto-generated constructors which will be copied to applications at compile time and will allocate an older memory layout. Call of any exported method of this class may access a memory outside the allocated objects or inside the older memory structure and result in crash or incorrect behavior of applications. 2) The memory layout and size of subclasses will be changed.

clipper.hpp
namespace ClipperLib
[+] class ClipperBase (1)
[+] class ClipperOffset (1)
[+] class PolyNode (2)
[+] class PolyTree (1)

to the top

Problems with Symbols, High Severity (1)

	Change	Effect
1	Parameters list has been changed.	The name of the appropriate symbol for this function on binary level has been changed from _ZN10ClipperLib12MinkowskiSumERKSt6vectorINS_8IntPointESaIS1_EERKS0_IS3_SaIS3_EERS7_NS_12PolyFillTypeEb to _ZN10ClipperLib12MinkowskiSumERKSt6vectorINS_8IntPointESaIS1_EERKS0_IS3_SaIS3_EERS7_b. This may cause "undefined reference" linker error in old client applications.

clipper.hpp, libpolyclipping.so.16.0.0
namespace ClipperLib
[+] MinkowskiSum ( Path const& pattern, Paths const& paths, Paths& solution, enum PolyFillType pathFillType, bool pathIsClosed ) (1)

to the top

Problems with Data Types, Medium Severity (2)

	Change	Effect
1	The layout of v-table has been changed for unknown reason.	Call of any method in this class may result in crash or incorrect behavior of applications.

Offset	Virtual Table (Old) - 16 entries	Virtual Table (New) - 16 entries
0	104u	96u
4	(int (*)(...))0	(int (*)(...))0
8	(int (*)(...))(& typeinfo)	(int (*)(...))(& typeinfo)
12	~Clipper	~Clipper
16	~Clipper	~Clipper
20	Clipper::Reset	Clipper::Reset
24	Clipper::ExecuteInternal	Clipper::ExecuteInternal
28	-104u	-96u
32	(int (*)(...))0	(int (*)(...))0
36	-104u	-96u
40	(int (*)(...))-0x000000068	(int (*)(...))-0x000000060
44	(int (*)(...))(& typeinfo)	(int (*)(...))(& typeinfo)
48	Clipper::_ZTv0_n12_N10ClipperLib7ClipperD1Ev	Clipper::_ZTv0_n12_N10ClipperLib7ClipperD1Ev
52	Clipper::_ZTv0_n12_N10ClipperLib7ClipperD0Ev	Clipper::_ZTv0_n12_N10ClipperLib7ClipperD0Ev
56	ClipperBase::Clear	ClipperBase::Clear
60	Clipper::_ZTv0_n20_N10ClipperLib7Clipper5ResetEv	Clipper::_ZTv0_n20_N10ClipperLib7Clipper5ResetEv

	Change	Effect
1	Type of field m_MinimaList has been changed from struct LocalMinima* (4 bytes) to ClipperBase::MinimaList (12 bytes).	1) Size of the inclusive type has been changed. 2) Previous accesses of applications and library functions to this field and fields at higher positions of the structure definition may be broken.

clipper.hpp
namespace ClipperLib
[+] class Clipper (1)
[+] class ClipperBase (1)

to the top

Problems with Data Types, Low Severity (4)

	Change	Effect
1	The pointer level of field m_CurrentLM has been decreased from 1 to 0.	The library functions will treat the value of this field as the lower-dimension array and will not read all elements. This may change the behavior of applications.
2	The pointer level of field m_MinimaList has been decreased from 1 to 0.	The library functions will treat the value of this field as the lower-dimension array and will not read all elements. This may change the behavior of applications.
3	Type of field m_CurrentLM has been changed from struct LocalMinima* to std::vector<struct LocalMinimum>::iterator.	Replacement of the field data type may indicate a change in the semantic meaning of the field.

	Change	Effect
1	Size of field m_polyNodes has been changed from 44 bytes to 48 bytes.	Size of the inclusive type has been changed.

clipper.hpp
namespace ClipperLib
[+] class ClipperBase (3)
[+] class ClipperOffset (1)

to the top

Other Changes in Data Types (1)

	Change	Effect
1	Type of field m_Scanbeam has been changed from std::set<long long,std::greater<long long> > (24 bytes) to Clipper::ScanbeamList (16 bytes).	No effect.

clipper.hpp
namespace ClipperLib
[+] class Clipper (1)

to the top

Header Files (1)

clipper.hpp

to the top

Shared Libraries (1)

libpolyclipping.so.16.0.0

to the top