Update GC library to 7.6.2

gc/.gitignore

@@ -12,8 +12,8 @@
 *.o
 *.obj
 
+*.gc.log
 .dirstamp
-/*.gc.log
 /*_bench.log
 /*_bench.trs
 /*test.log
@@ -23,6 +23,8 @@
 /add_gc_prefix
 /base_lib
 /bdw-gc.pc
+/bsd-libgc.a
+/bsd-libleak.a
 /c++
 /config.cache
 /config.log
@@ -31,6 +33,7 @@
 /cord/de
 /cord/de_win.rbj
 /cord/de_win.res
+/cord/tests/de_win.rbj
 /cord/tests/de_win.res
 /cordtest
 /core
@@ -42,20 +45,31 @@
 /gc.log
 /gcname
 /gctest
+/gctest_dyn_link
+/gctest_irix_dyn_link
 /hugetest
 /if_mach
 /if_not_there
 /initsecondarythread_test
 /leaktest
+/libalphagc.so
+/libgc.so
+/libirixgc.so
+/liblinuxgc.so
 /libtool
 /middletest
 /realloc_test
 /setjmp_test
 /smashtest
 /staticrootstest
 /subthreadcreate_test
+/sunos5gc.so
 /test-suite.log
+/test_atomic_ops
+/test_atomic_ops.log
+/test_atomic_ops.trs
 /test_cpp
+/test_cpp.cpp
 /test_cpp.log
 /test_cpp.trs
 /threadkey_test
@@ -65,7 +79,7 @@
 
 # Config, dependency and stamp files generated by configure:
 .deps/
-config.h
+/include/config.h
 config.h.in~
 stamp-h1
 
@@ -95,22 +109,32 @@ stamp-h1
 /test-driver
 
 # These files are generated by CMake:
+*.tlog
 /*.vcxproj
 /*.vcxproj.filters
 /CMakeCache.txt
 /CMakeFiles/
+/CTestTestfile.cmake
+/DartConfiguration.tcl
+/Testing/Temporary/
 /cmake_install.cmake
 /gc.sln
+/libgc*-dll.so
+/libgc*-lib.a
 /tests/*.vcxproj
 /tests/*.vcxproj.filters
+/tests/*test
 /tests/CMakeFiles/
+/tests/CTestTestfile.cmake
 /tests/Makefile
 /tests/cmake_install.cmake
+/tests/test_cpp
 
 # Rarely generated files (mostly by some Win/DOS compilers):
 /*.copied.c
 /*.csm
 /*.err
+/*.i
 /*.lb1
 /*.lnk
 /*.map
@@ -130,3 +154,15 @@ stamp-h1
 
 # Stuff from VS build system and IDE
 *.vcproj.*.user
+
+# Code analysis tools:
+*.c.gcov
+*.cc.gcov
+*.h.gcov
+*.sancov
+/.sv*-dir
+/cov-int
+/coverage.info
+/pvs-project.log
+/pvs-project.tasks
+/strace_out