Index: External/CMakeLists.txt
===================================================================
--- External/CMakeLists.txt
+++ External/CMakeLists.txt
@@ -1,4 +1,5 @@
 add_subdirectory(CUDA)
+add_subdirectory(gcc-c-torture)
 add_subdirectory(HMMER)
 add_subdirectory(Nurbs)
 add_subdirectory(Povray)
Index: External/gcc-c-torture/CMakeLists.txt
===================================================================
--- /dev/null
+++ External/gcc-c-torture/CMakeLists.txt
@@ -0,0 +1,49 @@
+include(External)
+llvm_externals_find(TEST_SUITE_GCC_C_TORTURE_ROOT "gcc-c-torture" "GCC C Torture Suite")
+if(TEST_SUITE_GCC_C_TORTURE_ROOT)
+
+  function(gcc_torture_dg_options_cflags File)
+    # Some files have dg-options which we need to pick up. These should be in
+    # the first line but often aren't.
+    #
+    # We also need to be careful not to pick up target-specific dg-options.
+    file(STRINGS ${File} FileLines)
+    foreach(FileLine ${FileLines})
+      # Looking for `dg-options "..."` without `{ target` afterwards (ignoring
+      # whitespace).
+      if(FileFirstLine MATCHES "dg-options \"([^\"]*)\" *[^{]")
+        # This is needed to turn the string into a list of CFLAGS
+        separate_arguments(FILE_CFLAGS UNIX_COMMAND ${CMAKE_MATCH_1})
+        list(APPEND CFLAGS ${FILE_CFLAGS})
+      endif()
+    endforeach()
+  endfunction()
+
+  # Execute-style tests
+  #
+  # These will compile and then execute
+  function(gcc_torture_execute_test File)
+    get_filename_component(Name ${File} NAME_WE)
+    set(_target "torture-${TORTURE_NAME_PREFIX}-${Name}")
+
+    gcc_torture_dg_options_cflags(${File})
+
+    llvm_test_executable_no_test(${_target} ${File})
+    llvm_test_run()
+    llvm_add_test_for_target(${_target})
+  endfunction()
+
+  macro(gcc_torture_subdir DIR)
+    string(REPLACE "/" "-" TORTURE_NAME_PREFIX ${DIR})
+    set(TORTURE_DIR "${TEST_SUITE_GCC_C_TORTURE_ROOT}/${DIR}")
+    add_subdirectory(${DIR})
+  endmacro()
+
+  # gcc_torture_subdir(compile)
+
+  gcc_torture_subdir(execute)
+  gcc_torture_subdir(execute/ieee)
+
+  file(COPY lit.local.cfg DESTINATION "${CMAKE_CURRENT_BINARY_DIR}")
+
+endif()
\ No newline at end of file
Index: External/gcc-c-torture/README
===================================================================
--- /dev/null
+++ External/gcc-c-torture/README
@@ -0,0 +1,15 @@
+# GCC C Torture Suite
+
+This external test suite requires an export of
+svn://gcc.gnu.org/svn/gcc/trunk/gcc/testsuite/gcc.c-torture at either
+llvm-test-suite/test-suite-externals/gcc-c-torture or at
+$TEST_SUITE_GCC_C_TORTURE_ROOT
+
+Last checked at SVN version 275024
+
+A command-line invocation to do a SVN Export at that revision might look like
+the following, if run from the root of llvm-test-suite:
+
+  $ svn export -r 275024 \
+    svn://gcc.gnu.org/svn/gcc/trunk/gcc/testsuite/gcc.c-torture \
+    test-suite-externals/gcc-c-torture
Index: External/gcc-c-torture/execute/CMakeLists.txt
===================================================================
--- /dev/null
+++ External/gcc-c-torture/execute/CMakeLists.txt
@@ -0,0 +1,188 @@
+# The list of tests to skip is probably too long for this file
+set(TestsToSkip
+  # Nested functions, unsupported in clang
+  20000822-1.c
+  20010209-1.c
+  20010605-1.c
+  20030501-1.c
+  20040520-1.c
+  20061220-1.c
+  20090219-1.c
+  920415-1.c
+  920428-2.c
+  920501-7.c
+  920612-2.c
+  920721-4.c
+  921017-1.c
+  921215-1.c
+  931002-1.c
+  comp-goto-2.c
+  nest-align-1.c
+  nest-stdar-1.c
+  nestfunc-1.c
+  nestfunc-2.c
+  nestfunc-3.c
+  nestfunc-5.c
+  nestfunc-6.c
+  nestfunc-7.c
+  pr22061-3.c
+  pr22061-4.c
+  pr24135.c
+  pr51447.c
+  pr71494.c
+
+  # Expects gnu89 inline behaviour
+  20001121-1.c
+  20020107-1.c
+  930526-1.c
+  961223-1.c
+  980608-1.c
+  bcp-1.c
+  loop-2c.c
+  p18298.c
+  restrict-1.c
+  unroll-1.c
+  va-arg-7.c
+  va-arg-8.c
+
+  # Variable length arrays in structs, unsupported in clang
+  20020412-1.c
+  20040308-1.c
+  20040423-1.c
+  20041218-2.c
+  20070919-1.c
+  align-nest.c
+  pr41935.c
+  pr82210.c
+
+  # Initialization of flexible array member unsupported in clang
+  pr28865.c
+
+  # Runtime failure even on clang x86
+  20021127-1.c
+  20031003-1.c
+  alloca-1.c
+  bitfld-3.c
+  bitfld-5.c
+  eeprof-1.c
+  pr32244-1.c
+  pr34971.c
+
+  # Clang has no __builtin_malloc
+  20071018-1.c
+  20071120-1.c
+  pr36765.c
+  pr43008.c
+  pr84339.c
+  pr84478.c
+  strlen-7.c
+
+  # Non-void function must return a value
+  920302-1.c
+  920501-3.c
+  920728-1.c
+
+  # Must link with libm
+  980709-1.c
+  float-floor.c
+
+  # x86 only
+  990413-2.c
+
+  # Unsupported builtins, even on x86 clang
+  builtin-bitops-1.c
+  pr39228.c
+  pr47237.c
+  pr78586.c
+  pr79327.c
+  va-arg-pack-1.c
+
+  # Requires mmap
+  loop-2f.c
+  loop-2g.c
+
+  # Link error, even on x86 clang
+  medce-1.c
+
+  # Clang does not support 'DD' suffix on floating constant
+  pr80692.c
+
+  # Requires definitions of stdout/stderr
+  fprintf-1.c
+  fprintf-chk-1.c
+  gofast.c
+  vfprintf-1.c
+  vfprintf-chk-1.c
+
+  # 64-bit Multiply-with-overflow expands to a __mulodi4, which is present in
+  # compiler-rt but not libgcc
+  pr71554.c
+  pr89434.c
+
+  # __muloti4 is present in compiler-rt but not libgcc
+  pr84169.c
+
+  # __assert_fail is not defined in newlib
+  pr58831.c
+
+  # No support for __builtin_longjmp/__builtin_setjmp. Also true of clang for
+  # AArch64.
+  built-in-setjmp.c
+  pr60003.c
+  pr64242.c
+  pr84521.c
+
+  # Test depends on Clang having the same __builtin_constant_p(x) behaviour as gcc.
+  # Fails on Clang x86-64 with optimisation enabled
+  builtin-constant.c
+
+  # pragma optimize("-option") is ignored by Clang
+  alias-1.c
+  pr79043.c
+
+  # Expects that function is always inlined
+  990208-1.c
+
+  # Checks optimiser-specific behaviour, also fails on Clang x86 with O1
+  printf-chk-1.c
+  vprintf-chk-1.c
+
+  # Test relies on undefined signed overflow behaviour (int foo - INT_MIN).
+  # Should really require -fwrapv
+  20040409-1.c
+  20040409-2.c
+  20040409-3.c
+
+  # clang doesn't support __builtin_shuffle
+  pr85331.c
+
+  # Fails on gcc too, newlib presumably newlib fails to support %hhd
+  pr78622.c
+
+  # __builtin_return_address(n) with n > 0 not guaranteed to give expected result
+  20010122-1.c
+)
+
+if(CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "riscv")
+  list(APPEND TestsToSkip
+    # clang complains the array is too large on RV64
+    991014-1.c
+
+    # Requires int128 support (not present on RV32)
+    pr84748.c
+
+    # Can't open file with newlib+pk+spike
+    fprintf-2.c
+    printf-2.c
+    user-printf.c
+    )
+endif()
+
+file(GLOB TestFiles "${TORTURE_DIR}/*.c")
+foreach(SkipFile ${TestsToSkip})
+  list(REMOVE_ITEM TestFiles "${TORTURE_DIR}/${SkipFile}")
+endforeach()
+
+foreach(File ${TestFiles})
+  gcc_torture_execute_test(${File})
+endforeach()
\ No newline at end of file
Index: External/gcc-c-torture/execute/ieee/CMakeLists.txt
===================================================================
--- /dev/null
+++ External/gcc-c-torture/execute/ieee/CMakeLists.txt
@@ -0,0 +1,18 @@
+set(TestsToSkip
+  # Must link with libm
+  20041213-1.c
+  mzero4.c
+
+  # Clang at O0 does not work out the code referencing the undefined symbol can
+  # never be executed
+  fp-cmp-7.c
+)
+
+file(GLOB TestFiles "${TORTURE_DIR}/*.c")
+foreach(SkipFile ${TestsToSkip})
+  list(REMOVE_ITEM TestFiles "${TORTURE_DIR}/${SkipFile}")
+endforeach()
+
+foreach(File ${TestFiles})
+  gcc_torture_execute_test(${File})
+endforeach()
\ No newline at end of file
Index: External/gcc-c-torture/lit.local.cfg
===================================================================
--- /dev/null
+++ External/gcc-c-torture/lit.local.cfg
@@ -0,0 +1 @@
+config.single_source = True