auto merge of #17432 : nick29581/rust/contrib, r=brson

[rust.git] / src / doc / complement-lang-faq.md

diff --git a/src/doc/complement-lang-faq.md b/src/doc/complement-lang-faq.md
index c5ddd180ee8e13186d23b6de106d3cd5bb6bb78a..8db7ba9424fc128beb9c1e4bdcb06f3cdf7bc15e 100644 (file)
--- a/src/doc/complement-lang-faq.md
+++ b/src/doc/complement-lang-faq.md
@@ -1,4 +1,4 @@
-% Language FAQ
+% The Rust Language FAQ
 
 ## Are there any big programs written in it yet? I want to read big samples.
 
@@ -83,7 +83,7 @@ We want to maintain the option to parametrize at runtime. We may eventually chan
 
 ## Why aren't values type-parametric? Why only items?
 
-Doing so would make type inference much more complex, and require the implementation strategy of runtime parametrization.
+Doing so would make type inference much more complex, and require the implementation strategy of runtime parameterization.
 
 ## Why are enumerations nominal and closed?
 
@@ -162,4 +162,15 @@ debugging linking in the compiler you might set
 `RUST_LOG=rustc::metadata::creader,rustc::util::filesearch,rustc::back::rpath`
 For a full description see [the logging crate][1].
 
+## How fast is Rust?
+
+As always, this question is difficult to answer. There's still a lot of work to
+do on speed, and depending on what you're benchmarking, Rust has variable
+performance.
+
+That said, it is an explicit goal of Rust to be as fast as C++ for most things.
+Language decisions are made with performance in mind, and we want Rust to be as
+fast as possible. Given that Rust is built on top of LLVM, any performance
+improvements in it also help us be faster.
+
 [1]:log/index.html