rt: bump log levels up by one, fix tautological-compare error (and permit turning off logging entirely).

src/libcore/core.rs

@@ -54,23 +54,23 @@ pub use coreops::ops::{Shl, Shr, Index};
 // warn-and-below.
 
 /// The error log level
-pub const error : u32 = 0_u32;
+pub const error : u32 = 1_u32;
 /// The warning log level
-pub const warn : u32 = 1_u32;
+pub const warn : u32 = 2_u32;
 /// The info log level
-pub const info : u32 = 2_u32;
+pub const info : u32 = 3_u32;
 /// The debug log level
-pub const debug : u32 = 3_u32;
+pub const debug : u32 = 4_u32;
 
 // A curious inner-module that's not exported that contains the binding
 // 'core' so that macro-expanded references to core::error and such
 // can be resolved within libcore.
 #[doc(hidden)] // FIXME #3538
 mod core {
-    pub const error : u32 = 0_u32;
-    pub const warn : u32 = 1_u32;
-    pub const info : u32 = 2_u32;
-    pub const debug : u32 = 3_u32;
+    pub const error : u32 = 1_u32;
+    pub const warn : u32 = 2_u32;
+    pub const info : u32 = 3_u32;
+    pub const debug : u32 = 4_u32;
 }
 
 // Similar to above. Some magic to make core testable.

src/librustc/rustc.rs

@@ -222,7 +222,7 @@ fn monitor(+f: fn~(diagnostic::emitter)) {
                 for [
                     ~"the compiler hit an unexpected failure path. \
                      this is a bug",
-                    ~"try running with RUST_LOG=rustc=0,::rt::backtrace \
+                    ~"try running with RUST_LOG=rustc=1,::rt::backtrace \
                      to get further details and report the results \
                      to github.com/mozilla/rust/issues"
                 ].each |note| {

src/rt/rust_log.cpp

@@ -168,7 +168,7 @@ struct log_directive {
 
 const size_t max_log_directives = 255;
 const size_t max_log_level = 255;
-const size_t default_log_level = 0;
+const size_t default_log_level = log_err;
 
 // This is a rather ugly parser for strings in the form
 // "crate1,crate2.mod3,crate3.x=1". Log levels are 0-255,

src/rt/rust_log.h

@@ -4,10 +4,10 @@
 
 #include "rust_globals.h"
 
-const uint32_t log_err = 0;
-const uint32_t log_warn = 1;
-const uint32_t log_info = 2;
-const uint32_t log_debug = 3;
+const uint32_t log_err = 1;
+const uint32_t log_warn = 2;
+const uint32_t log_info = 3;
+const uint32_t log_debug = 4;
 
 #define LOG(task, field, ...)                                   \
     DLOG_LVL(log_debug, task, task->sched_loop, field, __VA_ARGS__)