[Reland] Add RPATH to shared libraries

Adds a fix for components/crash/content/tools/generate_breakpad_symbols.py which
saw significant slowdown causing telemetry_unittests and
telemetry_perf_unittests to timeout on the Linux Debug bot.  On my machine, the
time for this script to run is reduced from ~4m30s to ~6s.

> Fixes libfontconfig.so not being able to find libfreetype_harfbuzz.so:
>
> $ ldd libfontconfig.so | grep freetype_harfbuzz
>   libfreetype_harfbuzz.so => not found
> $ ls libfreetype_harfbuzz.so
> libfreetype_harfbuzz.so

TBR=dpranke
R=thestig
CC=mmoroz
BUG=913070,911836,912366
CQ_INCLUDE_TRYBOTS=luci.chromium.try:linux_chromium_dbg_ng

Change-Id: I94faed54a4ea9d50b8db38ca8c41b65d26e2bd5f
Reviewed-on: https://chromium-review.googlesource.com/c/1371080Reviewed-by: Thomas Anderson <thomasanderson@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#615975}

build/config/BUILD.gn

@@ -385,6 +385,8 @@ config("shared_library_config") {
     configs += [ "//build/config/ios:ios_dynamic_flags" ]
   } else if (is_chromecast) {
     configs += [ "//build/config/chromecast:shared_library_config" ]
+  } else if (is_linux || current_os == "aix") {
+    configs += [ "//build/config/gcc:shared_library_config" ]
   }
 
   # If we're using the prebuilt instrumented libraries with the sanitizers, we

build/config/gcc/BUILD.gn

@@ -84,20 +84,24 @@ config("rpath_for_built_shared_libraries") {
   }
 }
 
+if (is_component_build && !is_android) {
+  # See the rpath_for... config above for why this is necessary for component
+  # builds.
+  executable_and_shared_library_configs_ =
+      [ ":rpath_for_built_shared_libraries" ]
+} else {
+  executable_and_shared_library_configs_ = []
+}
+
 # Settings for executables.
 config("executable_config") {
+  configs = executable_and_shared_library_configs_
   ldflags = [ "-pie" ]
   if (is_android) {
     ldflags += [
       "-Bdynamic",
       "-Wl,-z,nocopyreloc",
     ]
-  } else {
-    # See the rpath_for... config above for why this is necessary for component
-    # builds.
-    if (is_component_build) {
-      configs = [ ":rpath_for_built_shared_libraries" ]
-    }
   }
 
   if (!is_android && current_os != "aix") {
@@ -116,3 +120,8 @@ config("executable_config") {
     ]
   }
 }
+
+# Settings for shared libraries.
+config("shared_library_config") {
+  configs = executable_and_shared_library_configs_
+}

components/crash/content/tools/generate_breakpad_symbols.py

@@ -12,6 +12,7 @@ platforms is planned.
 import collections
 import errno
 import glob
+import multiprocessing
 import optparse
 import os
 import Queue
@@ -22,7 +23,7 @@ import sys
 import threading
 
 
-CONCURRENT_TASKS=4
+CONCURRENT_TASKS=multiprocessing.cpu_count()
 
 # The BINARY_INFO tuple describes a binary as dump_syms identifies it.
 BINARY_INFO = collections.namedtuple('BINARY_INFO',
@@ -60,7 +61,7 @@ def Resolve(path, exe_path, loader_path, rpaths):
 
 
 def GetSharedLibraryDependenciesLinux(binary):
-  """Return absolute paths to all shared library dependecies of the binary.
+  """Return absolute paths to all shared library dependencies of the binary.
 
   This implementation assumes that we're running on a Linux system."""
   # TODO(thakis): Figure out how to make this work for android
@@ -72,7 +73,7 @@ def GetSharedLibraryDependenciesLinux(binary):
   for line in ldd.splitlines():
     m = lib_re.match(line)
     if m:
-      result.append(m.group(1))
+      result.append(os.path.abspath(m.group(1)))
   return result
 
 
@@ -106,7 +107,7 @@ def GetDeveloperDirMac():
 
 
 def GetSharedLibraryDependenciesMac(binary, exe_path):
-  """Return absolute paths to all shared library dependecies of the binary.
+  """Return absolute paths to all shared library dependencies of the binary.
 
   This implementation assumes that we're running on a Mac system."""
   # realpath() serves two purposes:
@@ -164,7 +165,7 @@ def GetSharedLibraryDependenciesMac(binary, exe_path):
 
 
 def GetSharedLibraryDependencies(options, binary, exe_path):
-  """Return absolute paths to all shared library dependecies of the binary."""
+  """Return absolute paths to all shared library dependencies of the binary."""
   deps = []
   if sys.platform.startswith('linux'):
     deps = GetSharedLibraryDependenciesLinux(binary)
@@ -183,6 +184,29 @@ def GetSharedLibraryDependencies(options, binary, exe_path):
   return result
 
 
+def GetTransitiveDependencies(options):
+  """Return absolute paths to the transitive closure of all shared library
+     dependencies of the binary, along with the binary itself."""
+  binary = os.path.abspath(options.binary)
+  exe_path = os.path.dirname(binary)
+  if sys.platform.startswith('linux'):
+    # 'ldd' returns all transitive dependencies for us.
+    deps = set(GetSharedLibraryDependencies(options, binary, exe_path))
+    deps.add(binary)
+    return list(deps)
+  if sys.platform == 'darwin':
+    binaries = set([binary])
+    queue = [binary]
+    while queue:
+      deps = GetSharedLibraryDependencies(options, queue.pop(0), exe_path)
+      new_deps = set(deps) - binaries
+      binaries |= new_deps
+      queue.extend(list(new_deps))
+    return binaries
+  print "Platform not supported."
+  sys.exit(1)
+
+
 def mkdir_p(path):
   """Simulates mkdir -p."""
   try:
@@ -328,14 +352,7 @@ def main():
     return 1
 
   # Build the transitive closure of all dependencies.
-  binaries = set([options.binary])
-  queue = [options.binary]
-  exe_path = os.path.dirname(options.binary)
-  while queue:
-    deps = GetSharedLibraryDependencies(options, queue.pop(0), exe_path)
-    new_deps = set(deps) - binaries
-    binaries |= new_deps
-    queue.extend(list(new_deps))
+  binaries = GetTransitiveDependencies(options)
 
   GenerateSymbols(options, binaries)