8.63. gcc

Bug Fixes

BZ#858351

Previously, the GNU Compiler Collection (GCC) did not handle compiling partial specialization invalid C++ code correctly. As a consequence, GCC could terminate unexpectedly with a segmentation fault. The bug has been fixed and GCC now provides a translation-time error instead of crashing.

BZ#875472

Previously, the GNU Compiler Collection (GCC) did not handle loop vectorization correctly. Consequently, GCC could terminate with a segmentation fault. With this update, GCC correctly ignores the debug statements when the vectorizer is looking for a loop-exit PHI node, and GCC now compiles the code as expected.

BZ#1008798

Previously, after compiling the source code of a program using the "-fprofile-arcs" and "-ftest-coverage" command-line options, the program was run and the gcov utility was started, but after that, a new source code file was created and gcov was started again. As a consequence, gcov damaged the existing .gcda files. After this update, functions are properly restored if a failure occurs, and gcov no longer damages other files.

BZ#1027003

Previously, if an invalid code in gnu++11 mode used an initializer list with an invalid value in its constructor, the g++ compiler terminated with a segmentation fault. With this update, the constructor is better tested for incorrect values, and g++ no longer crashes in the described scenario.

BZ#1061435

Previously, the Clang compiler did not handle certain headers correctly. As a consequence, a program using the typeinfo and exception headers failed to compile, and an "incomplete type" error message was displayed. With this update, the exception header in the libstdc++ library has been adjusted, and programs now compile as expected with the Clang compiler.

BZ#1085442

Previously, the standard uncaught_exception() function returned the "True" value even when the initialization of the exception object was not complete. As a consequence, the GNU Compiler Collection (GCC) could generate wrong code. With this update, uncaught_exception() returns the "True" value only after the exception object is created, and GCC always generates correct code as expected.

BZ#1087806

Prior to this update, the g++ compiler rejected code that tried to pass a type with a non-trivial copy constructor through variable arguments. As a consequence, programs compiled with the GNU Compiler Collection (GCC) terminated unexpectedly with an "Illegal instruction" error message. With this update g++ now accepts the code because it treats passing variadic arguments of non-trivial types as a pass-by-invisible reference.

BZ#1113793

Previously, the gfortran compiler did not correctly handle compiling code that involved invalid old-style initialization for derived type components. As a consequence, gfortran could terminate unexpectedly with a segmentation fault. A patch has been applied to address this bug, and the code is now properly rejected when needed, and an appropriate error message is displayed.

BZ#1113878

Larger aggregate contains the same fields as the smaller one with just some fields added at the end. Prior to this update, optimizing code that contained conversion from a larger aggregate to a smaller aggregate could cause the GNU Compiler Collection (GCC) to generate incorrect code. Consequently, using GCC with turned on optimizations failed and a segmentation fault occurred. With this update, conversions between aggregates with different sizes are never considered useless, and GCC no longer generates incorrect code in the described situation.

Enhancements

BZ#1099549

OpenMP 4.0 support has been added to the GNU OpenMP library, which allows applications built with DTS 3.0 and using OpenMP to link on Red Hat Enterprise Linux 6.