win: Simplify incremental linking flags setup.

We had a bunch of workarounds to get link.exe not use /incremental
for very large binaries.

Since we no longer use link.exe, remove those workarounds, and
since this removes all reference to a bunch of configs, remove
the configs as well.

Inline all that remains into default_incremental_linking.
(There's more that can be simplified here, but one thing
at a time.)

Bug: 1053958
Change-Id: I4cb123ef1a45fdbcd16d09211e55715095744a46
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2079088
Auto-Submit: Nico Weber <thakis@chromium.org>
Reviewed-by: Hans Wennborg <hans@chromium.org>
Reviewed-by: Bo <boliu@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745169}

build/config/win/BUILD.gn

@@ -514,52 +514,24 @@ config("windowed") {
 
 # Incremental linking ----------------------------------------------------------
 
-incremental_linking_on_switch = [ "/INCREMENTAL" ]
-if ((!is_debug && !is_component_build) || !use_lld) {
-  incremental_linking_off_switch = [ "/INCREMENTAL:NO" ]
-}
-if (use_lld) {
-  incremental_linking_on_switch += [ "/OPT:NOREF" ]
-}
-
-# Enable incremental linking for debug builds and all component builds - any
-# builds where performance is not job one.
-if (is_debug || is_component_build) {
-  default_incremental_linking_switch = incremental_linking_on_switch
-} else {
-  default_incremental_linking_switch = incremental_linking_off_switch
-}
-
 # Applies incremental linking or not depending on the current configuration.
 config("default_incremental_linking") {
-  ldflags = default_incremental_linking_switch
-}
-
-# Explicitly on or off incremental linking
-config("incremental_linking") {
-  ldflags = incremental_linking_on_switch
-}
-config("no_incremental_linking") {
-  # Projects disable incremental linking to work around ilk file issues with
-  # link.exe. lld doesn't use ilk files and doesn't really have an incremental
-  # link mode; the only effect of the flag is that the .lib file timestamp isn't
-  # updated if the .lib doesn't change.
-  if (!use_lld) {
-    ldflags = incremental_linking_off_switch
-  }
-}
-
-# Some large modules can't handle incremental linking in some situations. This
-# config should be applied to large modules to turn off incremental linking
-# when it won't work.
-config("default_large_module_incremental_linking") {
-  if (use_lld || symbol_level == 0 ||
-      (current_cpu == "x86" && is_component_build)) {
-    # In these configurations, ilk file sizes stay low enough that we can
-    # link incrementally.
-    ldflags = default_incremental_linking_switch
+  # Enable incremental linking for debug builds and all component builds - any
+  # builds where performance is not job one.
+  # TODO(thakis): Always turn this on with lld, no reason not to.
+  if (is_debug || is_component_build) {
+    ldflags = [ "/INCREMENTAL" ]
+    if (use_lld) {
+      # lld doesn't use ilk files and doesn't really have an incremental link
+      # mode; the only effect of the flag is that the .lib file timestamp isn't
+      # updated if the .lib doesn't change.
+      # TODO(thakis): Why pass /OPT:NOREF for lld, but not otherwise?
+      # TODO(thakis): /INCREMENTAL is on by default in link.exe, but not in
+      # lld.
+      ldflags += [ "/OPT:NOREF" ]
+    }
   } else {
-    ldflags = incremental_linking_off_switch
+    ldflags = [ "/INCREMENTAL:NO" ]
   }
 }
 

chrome/BUILD.gn

@@ -398,14 +398,6 @@ if (is_win) {
       configs += [ "//build/config/win:delayloads_not_for_child_dll" ]
     }
 
-    if (!is_component_build) {
-      # This is a large module that can't do incremental linking in some
-      # cases.
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
-    }
-
     if (use_aura) {
       deps += [ "//ui/compositor" ]
     }

chrome/browser/safe_browsing/incident_reporting/verifier_test/BUILD.gn

@@ -10,11 +10,6 @@ shared_library("verifier_test_dll_1") {
     "verifier_test_dll.cc",
     "verifier_test_dll_1.def",
   ]
-
-  # Unconditionally disable incremental linking for these modules so that
-  # their exports do not go through an ILT jmp stub.
-  configs -= [ "//build/config/win:default_incremental_linking" ]
-  configs += [ "//build/config/win:no_incremental_linking" ]
 }
 
 shared_library("verifier_test_dll_2") {
@@ -23,6 +18,4 @@ shared_library("verifier_test_dll_2") {
     "verifier_test_dll.cc",
     "verifier_test_dll_2.def",
   ]
-  configs -= [ "//build/config/win:default_incremental_linking" ]
-  configs += [ "//build/config/win:no_incremental_linking" ]
 }

chrome/test/BUILD.gn

@@ -1635,9 +1635,6 @@ if (!is_android) {
         # TODO(halyavin) NaCl on Windows can't open debug stub socket in
         # browser process as needed by this test. See http://crbug.com/157312.
         sources -= [ "../browser/nacl_host/test/gdb_debug_stub_browsertest.cc" ]
-        configs -= [ "//build/config/win:default_incremental_linking" ]
-        configs +=
-            [ "//build/config/win:default_large_module_incremental_linking" ]
       }
       if (is_linux) {
         data_deps += [ "//components/nacl/loader:nacl_helper" ]
@@ -5242,13 +5239,6 @@ test("unit_tests") {
     deps += [ "//rlz:test_support" ]
   }
   if (is_win) {
-    if (!is_component_build) {
-      # The PDB gets too large for incremental linking.
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
-    }
-
     sources += [
       "../browser/notifications/win/notification_image_retainer_unittest.cc",
       "../browser/notifications/win/notification_template_builder_unittest.cc",
@@ -6024,10 +6014,6 @@ if (!is_android) {
         "//ui/resources",
       ]
 
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
-
       libs = [
         "oleacc.lib",
         "runtimeobject.lib",
@@ -6436,10 +6422,6 @@ if (!is_fuchsia && !is_android) {
         "//third_party/wtl",
         "//ui/resources",
       ]
-
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
     }
     if (is_chromeos) {
       sources += [
@@ -6505,9 +6487,6 @@ if (!is_fuchsia && !is_android) {
         "//third_party/wtl",
         "//ui/resources",
       ]
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
     }
 
     if (toolkit_views) {
@@ -6668,10 +6647,6 @@ if (!is_fuchsia && !is_android) {
         "//third_party/wtl",
         "//ui/resources",
       ]
-
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
     }
   }
 

content/shell/BUILD.gn

@@ -625,11 +625,6 @@ if (is_android) {
 
     if (is_win) {
       deps += [ "//sandbox" ]
-
-      # This is a large module that can't do incremental linking in some cases.
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
       if (win_console_app) {
         defines += [ "WIN_CONSOLE_APP" ]
       } else {

third_party/blink/renderer/core/BUILD.gn

@@ -224,18 +224,6 @@ component("core") {
     "//third_party/blink/renderer/platform/wtf",
   ]
 
-  if (is_win && is_debug && is_component_build && current_cpu == "x64") {
-    # Incremental linking fails when the .ilk file gets too large.
-    # 64-bit debug builds with full symbols trigger this problem, so we turn
-    # off incremental linking in that configuration.
-    # For fastest builds, use component release builds without debug
-    # information.
-    # VC++ bug filed for 64-bit debug incremental link failures:
-    # https://connect.microsoft.com/VisualStudio/feedback/details/2846790
-    configs -= [ "//build/config/win:default_incremental_linking" ]
-    configs += [ "//build/config/win:no_incremental_linking" ]
-  }
-
   public_configs = [ ":core_include_dirs" ]
 
   if (is_mac) {

weblayer/shell/BUILD.gn

@@ -246,11 +246,6 @@ if (is_android) {
 
     if (is_win) {
       deps += [ "//sandbox" ]
-
-      # This is a large module that can't do incremental linking in some cases.
-      configs -= [ "//build/config/win:default_incremental_linking" ]
-      configs +=
-          [ "//build/config/win:default_large_module_incremental_linking" ]
       if (win_console_app) {
         defines += [ "WIN_CONSOLE_APP" ]
       } else {