Use a Raspbian sysroot for armhf-debian builds

This has a newer libc than the linaro toolchain we were using, which is
necessary for using some prebuilt shared objects.

Change-Id: Id4bcf3b1a18300aa40c77cda60050e3987e81dd1
diff --git a/tools/cpp/CROSSTOOL b/tools/cpp/CROSSTOOL
index 20f47e3..c15eddf 100644
--- a/tools/cpp/CROSSTOOL
+++ b/tools/cpp/CROSSTOOL
@@ -914,7 +914,7 @@
   needsPic: true
   compiler_flag: "-target"
   compiler_flag: "armv7a-arm-linux-gnueabif"
-  compiler_flag: "--sysroot=external/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc"
+  compiler_flag: "--sysroot=external/armhf_debian_rootfs"
   compiler_flag: "-mfloat-abi=hard"
   compiler_flag: "-mfpu=vfpv3-d16"
   compiler_flag: "-nostdinc"
@@ -931,7 +931,9 @@
   compiler_flag: "-isystem"
   compiler_flag: "external/linaro_linux_gcc_repo/include/c++/7.4.1"
   compiler_flag: "-isystem"
-  compiler_flag: "external/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc/usr/include"
+  compiler_flag: "external/armhf_debian_rootfs/usr/include"
+  compiler_flag: "-isystem"
+  compiler_flag: "external/armhf_debian_rootfs/usr/include/arm-linux-gnueabihf"
   compiler_flag: "-isystem"
   compiler_flag: "external/org_frc971/third_party"
   compiler_flag: "-D__STDC_FORMAT_MACROS"
@@ -960,12 +962,14 @@
   compiler_flag: "-ggdb3"
   linker_flag: "-target"
   linker_flag: "armv7a-arm-linux-gnueabif"
-  linker_flag: "--sysroot=external/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc"
+  linker_flag: "--sysroot=external/armhf_debian_rootfs"
   linker_flag: "-lstdc++"
   linker_flag: "-Ltools/cpp/linaro_linux_gcc/clang_more_libs"
-  linker_flag: "-Lexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/lib"
-  linker_flag: "-Lexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc/lib"
-  linker_flag: "-Lexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc/usr/lib"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/usr/lib/gcc/arm-linux-gnueabihf/8"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/lib/arm-linux-gnueabihf"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/usr/lib/arm-linux-gnueabihf"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/lib"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/usr/lib"
   linker_flag: "-Lexternal/linaro_linux_gcc_repo/lib/gcc/arm-linux-gnueabihf/7.4.1"
   linker_flag: "-Bexternal/linaro_linux_gcc_repo/lib/gcc/arm-linux-gnueabihf/7.4.1"
   linker_flag: "-Bexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/bin"
@@ -990,12 +994,8 @@
     mode: DYNAMIC
   }
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/usr/include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/usr/lib/include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.4.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@armhf_debian_rootfs//usr/include)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//include)%/c++/7.4.1"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.4.1/include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.4.1/include-fixed)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//lib/gcc/arm-linux-gnueabihf/7.4.1/include)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//lib/gcc/arm-linux-gnueabihf/7.4.1/include-fixed)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/include)%/c++/7.4.1"
diff --git a/tools/cpp/linaro_linux_gcc/BUILD b/tools/cpp/linaro_linux_gcc/BUILD
index b5ea5a5..7b7f3e5 100644
--- a/tools/cpp/linaro_linux_gcc/BUILD
+++ b/tools/cpp/linaro_linux_gcc/BUILD
@@ -1,13 +1,5 @@
 package(default_visibility = ["//tools/cpp:__pkg__"])
 
-cc_library(
-    name = "libpthread",
-    srcs = [
-        "clang_more_libs/libpthread.so",
-    ],
-    visibility = ["//visibility:public"],
-)
-
 filegroup(
     name = "gcc",
     srcs = [
diff --git a/tools/cpp/linaro_linux_gcc/clang_more_libs/libpthread.so b/tools/cpp/linaro_linux_gcc/clang_more_libs/libpthread.so
deleted file mode 100644
index 71f034f..0000000
--- a/tools/cpp/linaro_linux_gcc/clang_more_libs/libpthread.so
+++ /dev/null
@@ -1,5 +0,0 @@
-/* GNU ld script
-   Use the shared library, but some functions are only in
-   the static library, so try that secondarily.  */
-OUTPUT_FORMAT(elf32-littlearm)
-GROUP ( libpthread.so.0 libpthread_nonshared.a )
diff --git a/tools/cpp/static_crosstool.pb b/tools/cpp/static_crosstool.pb
index 8552dff..7261677 100644
--- a/tools/cpp/static_crosstool.pb
+++ b/tools/cpp/static_crosstool.pb
@@ -939,7 +939,7 @@
 
   compiler_flag: "-target"
   compiler_flag: "armv7a-arm-linux-gnueabif"
-  compiler_flag: "--sysroot=external/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc"
+  compiler_flag: "--sysroot=external/armhf_debian_rootfs"
   compiler_flag: "-mfloat-abi=hard"
   compiler_flag: "-mfpu=vfpv3-d16"
 
@@ -957,27 +957,29 @@
   compiler_flag: "-isystem"
   compiler_flag: "external/linaro_linux_gcc_repo/include/c++/7.4.1"
   compiler_flag: "-isystem"
-  compiler_flag: "external/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc/usr/include"
+  compiler_flag: "external/armhf_debian_rootfs/usr/include"
+  compiler_flag: "-isystem"
+  compiler_flag: "external/armhf_debian_rootfs/usr/include/arm-linux-gnueabihf"
+  compiler_flag: "-isystem"
+  compiler_flag: "external/org_frc971/third_party"
 
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/usr/include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/usr/lib/include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.4.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@armhf_debian_rootfs//usr/include)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//include)%/c++/7.4.1"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.4.1/include)%"
-  cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.4.1/include-fixed)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//lib/gcc/arm-linux-gnueabihf/7.4.1/include)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//lib/gcc/arm-linux-gnueabihf/7.4.1/include-fixed)%"
   cxx_builtin_include_directory: "%package(@linaro_linux_gcc_repo//arm-linux-gnueabihf/include)%/c++/7.4.1"
 
   linker_flag: "-target"
   linker_flag: "armv7a-arm-linux-gnueabif"
-  linker_flag: "--sysroot=external/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc"
+  linker_flag: "--sysroot=external/armhf_debian_rootfs"
   linker_flag: "-lstdc++"
   linker_flag: "-Ltools/cpp/linaro_linux_gcc/clang_more_libs"
-  linker_flag: "-Lexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/lib"
-  linker_flag: "-Lexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc/lib"
-  linker_flag: "-Lexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/libc/usr/lib"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/usr/lib/gcc/arm-linux-gnueabihf/8"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/lib/arm-linux-gnueabihf"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/usr/lib/arm-linux-gnueabihf"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/lib"
+  linker_flag: "-Lexternal/armhf_debian_rootfs/usr/lib"
   linker_flag: "-Lexternal/linaro_linux_gcc_repo/lib/gcc/arm-linux-gnueabihf/7.4.1"
   linker_flag: "-Bexternal/linaro_linux_gcc_repo/lib/gcc/arm-linux-gnueabihf/7.4.1"
   linker_flag: "-Bexternal/linaro_linux_gcc_repo/arm-linux-gnueabihf/bin"