rust/0001-std-stop-backtracing-when-the-frames-are-full.patch

From f4e8d57b6ad6f599de54c020ba185db83cb011a3 Mon Sep 17 00:00:00 2001
From: Josh Stone <jistone@redhat.com>
Date: Thu, 16 Aug 2018 11:26:27 -0700
Subject: [PATCH] std: stop backtracing when the frames are full

---
 src/libstd/sys/cloudabi/backtrace.rs           | 18 ++++++++++--------
 src/libstd/sys/redox/backtrace/tracing.rs      | 18 ++++++++++--------
 src/libstd/sys/unix/backtrace/tracing/gcc_s.rs | 18 ++++++++++--------
 3 files changed, 30 insertions(+), 24 deletions(-)

diff --git a/src/libstd/sys/cloudabi/backtrace.rs b/src/libstd/sys/cloudabi/backtrace.rs
index 1b970187558c..2c43b5937ce5 100644
--- a/src/libstd/sys/cloudabi/backtrace.rs
+++ b/src/libstd/sys/cloudabi/backtrace.rs
@@ -64,6 +64,10 @@ extern "C" fn trace_fn(
     arg: *mut libc::c_void,
 ) -> uw::_Unwind_Reason_Code {
     let cx = unsafe { &mut *(arg as *mut Context) };
+    if cx.idx >= cx.frames.len() {
+        return uw::_URC_NORMAL_STOP;
+    }
+
     let mut ip_before_insn = 0;
     let mut ip = unsafe { uw::_Unwind_GetIPInfo(ctx, &mut ip_before_insn) as *mut libc::c_void };
     if !ip.is_null() && ip_before_insn == 0 {
@@ -73,14 +77,12 @@ extern "C" fn trace_fn(
     }
 
     let symaddr = unsafe { uw::_Unwind_FindEnclosingFunction(ip) };
-    if cx.idx < cx.frames.len() {
-        cx.frames[cx.idx] = Frame {
-            symbol_addr: symaddr as *mut u8,
-            exact_position: ip as *mut u8,
-            inline_context: 0,
-        };
-        cx.idx += 1;
-    }
+    cx.frames[cx.idx] = Frame {
+        symbol_addr: symaddr as *mut u8,
+        exact_position: ip as *mut u8,
+        inline_context: 0,
+    };
+    cx.idx += 1;
 
     uw::_URC_NO_REASON
 }
diff --git a/src/libstd/sys/redox/backtrace/tracing.rs b/src/libstd/sys/redox/backtrace/tracing.rs
index bb70ca360370..c0414b78f8d6 100644
--- a/src/libstd/sys/redox/backtrace/tracing.rs
+++ b/src/libstd/sys/redox/backtrace/tracing.rs
@@ -68,6 +68,10 @@ pub fn unwind_backtrace(frames: &mut [Frame])
 extern fn trace_fn(ctx: *mut uw::_Unwind_Context,
                    arg: *mut libc::c_void) -> uw::_Unwind_Reason_Code {
     let cx = unsafe { &mut *(arg as *mut Context) };
+    if cx.idx >= cx.frames.len() {
+        return uw::_URC_NORMAL_STOP;
+    }
+
     let mut ip_before_insn = 0;
     let mut ip = unsafe {
         uw::_Unwind_GetIPInfo(ctx, &mut ip_before_insn) as *mut libc::c_void
@@ -94,14 +98,12 @@ extern fn trace_fn(ctx: *mut uw::_Unwind_Context,
         unsafe { uw::_Unwind_FindEnclosingFunction(ip) }
     };
 
-    if cx.idx < cx.frames.len() {
-        cx.frames[cx.idx] = Frame {
-            symbol_addr: symaddr as *mut u8,
-            exact_position: ip as *mut u8,
-            inline_context: 0,
-        };
-        cx.idx += 1;
-    }
+    cx.frames[cx.idx] = Frame {
+        symbol_addr: symaddr as *mut u8,
+        exact_position: ip as *mut u8,
+        inline_context: 0,
+    };
+    cx.idx += 1;
 
     uw::_URC_NO_REASON
 }
diff --git a/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs b/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs
index 1b92fc0e6ad0..6e8415686792 100644
--- a/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs
+++ b/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs
@@ -68,6 +68,10 @@ pub fn unwind_backtrace(frames: &mut [Frame])
 extern fn trace_fn(ctx: *mut uw::_Unwind_Context,
                    arg: *mut libc::c_void) -> uw::_Unwind_Reason_Code {
     let cx = unsafe { &mut *(arg as *mut Context) };
+    if cx.idx >= cx.frames.len() {
+        return uw::_URC_NORMAL_STOP;
+    }
+
     let mut ip_before_insn = 0;
     let mut ip = unsafe {
         uw::_Unwind_GetIPInfo(ctx, &mut ip_before_insn) as *mut libc::c_void
@@ -94,14 +98,12 @@ extern fn trace_fn(ctx: *mut uw::_Unwind_Context,
         unsafe { uw::_Unwind_FindEnclosingFunction(ip) }
     };
 
-    if cx.idx < cx.frames.len() {
-        cx.frames[cx.idx] = Frame {
-            symbol_addr: symaddr as *mut u8,
-            exact_position: ip as *mut u8,
-            inline_context: 0,
-        };
-        cx.idx += 1;
-    }
+    cx.frames[cx.idx] = Frame {
+        symbol_addr: symaddr as *mut u8,
+        exact_position: ip as *mut u8,
+        inline_context: 0,
+    };
+    cx.idx += 1;
 
     uw::_URC_NO_REASON
 }
-- 
2.17.1