Auto merge of #14251 - vvuk:servobuild-rustflags, r=ConnorGBrewster

Support build.rustflags in .servobuild

Add ability to specify rustflags in .servobuild.

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python/servo/command_base.py

@@ -297,6 +297,7 @@ class CommandBase(object):
         self.config["build"].setdefault("mode", "")
         self.config["build"].setdefault("debug-mozjs", False)
         self.config["build"].setdefault("ccache", "")
+        self.config["build"].setdefault("rustflags", "")
 
         self.config.setdefault("android", {})
         self.config["android"].setdefault("sdk", "")
@@ -486,6 +487,9 @@ class CommandBase(object):
 
         env['RUSTDOC'] = path.join(self.context.topdir, 'etc', 'rustdoc-with-private')
 
+        if self.config["build"]["rustflags"]:
+            env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " " + self.config["build"]["rustflags"]
+
         # Don't run the gold linker if on Windows https://github.com/servo/servo/issues/9499
         if self.config["tools"]["rustc-with-gold"] and sys.platform not in ("win32", "msys"):
             if subprocess.call(['which', 'ld.gold'], stdout=PIPE, stderr=PIPE) == 0:

servobuild.example

@@ -38,6 +38,8 @@ android = false
 debug-mozjs = false
 # Set to the path to your ccache binary to enable caching of compiler outputs
 #ccache = "/usr/local/bin/ccache"
+# Any optional flags that will be added to $RUSTFLAGS
+#rustflags = ""
 
 # Android information
 [android]