Remove obsoleted target_arch==armv7 from opus.gyp.

third_party/opus/BUILD.gn

Index: third_party/opus/BUILD.gn
diff --git a/third_party/opus/BUILD.gn b/third_party/opus/BUILD.gn
index 686a6b958dcd0bffe8fc30b22568f00c06f89040..aa646df121e5faa3f8b7e47bbfd38b3a0b853d00 100644
--- a/third_party/opus/BUILD.gn
+++ b/third_party/opus/BUILD.gn
@@ -5,14 +5,15 @@
 import("//build/config/arm.gni")
 
 # If fixed point implementation shall be used (otherwise float).
-use_opus_fixed_point = ((is_android || is_chromeos ||
-                         (is_ios && arm_version == 7)) && cpu_arch == "arm")
+use_opus_fixed_point = (cpu_arch == "arm" || cpu_arch == "arm64")
 
 # If ARM optimizations shall be used to accelerate performance.
-use_opus_arm_optimization = use_opus_fixed_point
+use_opus_arm_optimization = (cpu_arch == "arm")
 
 # If OPUS Run Time CPU Detections (RTCD) shall be used.
-use_opus_rtcd = ((is_android || is_chromeos) && cpu_arch == "arm")
+# Based on the conditions in celt/arm/armcpu.c:
+# defined(_MSC_VER) || defined(__linux__).
+use_opus_rtcd = (cpu_arch == "arm" && (is_win || is_android || is_desktop_linux || is_chromeos))
 
 config("opus_config") {
   include_dirs = [
@@ -83,6 +84,11 @@ source_set("opus") {
     ]
   }
 
+  if (is_posix && (cpu_arch == "arm" || cpu_arch == "arm64")) {
+    cflags -= [ "-Os" ]

[ajm, 2014/10/24 19:57:29]

I want to remove -Os from the "global" cflags, but I get this error:
ERROR at //third_party/opus/BUILD.gn:88:5: Undefined variable for -=.
    cflags -= [ "-Os" ]
    ^-----
I don't have something with this name in scope now.

This makes sense locally. How do I modify the "global" cflags? Do I just need to
make sure cflags is defined here locally (i.e. something like cflags = [] above
this)? I've marked the equivalent gyp operation.

[brettw, 2014/10/24 23:36:18]

# Note addition of "is_release" in the condition:
if (is_release && is_posix && (cpu_arch == "arm" || cpu_arch == "arm64")) {
  configs -= [ "//build/config/compiler:optimize" ]
  configs += [ "//build/config/compiler:optimize_max" ]
}

This is more-or-less covered in the cookbook
https://code.google.com/p/chromium/wiki/GNCookbook under the "optimize: max"
section. BTW, optimize:max is probably what you should be doing in GYP instead
of manually messing with the flags.

[ajm, 2014/10/24 23:53:51]

Thanks, updated as advised.
I looked into this, but it seems optimize only has an impact on Windows?
https://code.google.com/p/chromium/codesearch#chromium/src/build/common.gypi&...

(At least I couldn't see anywhere else it would have an impact.)

[brettw, 2014/10/25 15:58:06]

Oh yes, you're right. I now remember being offended by that asymmetry.

+    cflags += [ "-O3" ]
+  }
+
   if (use_opus_fixed_point) {
     sources += gypi_values.opus_fixed_sources