authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2019-02-23 13:19:06-05:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2019-02-23 13:19:06-05:00
log00d8f4a1bb634ec5b0569e6ff6c2679ade2bd6b0
treec06f376d383800d703be682e7ad5ee258e56788b
parent6fd8d455bcc6765e7411fa00d23dca1eb270aac9
signaturelock-open Commit is signed but in an unrecognized format.

introduce std.debug.captureStackTrace

and fix the implementation of writeStackTrace it was printing the first frame in the wrong place

2 files changed, 69 insertions(+), 16 deletions(-)

std/debug/index.zig+62-12
......@@ -90,9 +90,60 @@ pub fn dumpCurrentStackTrace(start_addr: ?usize) void {
9090 };
9191}
9292
93/// Returns a slice with the same pointer as addresses, with a potentially smaller len.
94/// On Windows, when first_address is not null, we ask for at least 32 stack frames,
95/// and then try to find the first address. If addresses.len is more than 32, we
96/// capture that many stack frames exactly, and then look for the first address,
97/// chopping off the irrelevant frames and shifting so that the returned addresses pointer
98/// equals the passed in addresses pointer.
99pub fn captureStackTrace(first_address: ?usize, stack_trace: *builtin.StackTrace) void {
100 switch (builtin.os) {
101 builtin.Os.windows => {
102 const addrs = stack_trace.instruction_addresses;
103 const u32_addrs_len = @intCast(u32, addrs.len);
104 const first_addr = first_address orelse {
105 stack_trace.index = windows.RtlCaptureStackBackTrace(
106 0,
107 u32_addrs_len,
108 @ptrCast(**c_void, addrs.ptr),
109 null,
110 );
111 return;
112 };
113 var addr_buf_stack: [32]usize = undefined;
114 const addr_buf = if (addr_buf_stack.len > addrs.len) addr_buf_stack[0..] else addrs;
115 const n = windows.RtlCaptureStackBackTrace(0, u32_addrs_len, @ptrCast(**c_void, addr_buf.ptr), null);
116 const first_index = for (addr_buf[0..n]) |addr, i| {
117 if (addr == first_addr) {
118 break i;
119 }
120 } else {
121 stack_trace.index = 0;
122 return;
123 };
124 const slice = addr_buf[first_index..n];
125 // We use a for loop here because slice and addrs may alias.
126 for (slice) |addr, i| {
127 addrs[i] = addr;
128 }
129 stack_trace.index = slice.len;
130 },
131 else => {
132 var it = StackIterator.init(first_address);
133 for (stack_trace.instruction_addresses) |*addr, i| {
134 addr.* = it.next() orelse {
135 stack_trace.index = i;
136 return;
137 };
138 }
139 stack_trace.index = stack_trace.instruction_addresses.len;
140 },
141 }
142}
143
93144/// Tries to print a stack trace to stderr, unbuffered, and ignores any error returned.
94145/// TODO multithreaded awareness
95pub fn dumpStackTrace(stack_trace: *const builtin.StackTrace) void {
146pub fn dumpStackTrace(stack_trace: builtin.StackTrace) void {
96147 const stderr = getStderrStream() catch return;
97148 const debug_info = getSelfDebugInfo() catch |err| {
98149 stderr.print("Unable to dump stack trace: Unable to open debug info: {}\n", @errorName(err)) catch return;
......@@ -141,7 +192,7 @@ pub fn panicExtra(trace: ?*const builtin.StackTrace, first_trace_addr: ?usize, c
141192 const stderr = getStderrStream() catch os.abort();
142193 stderr.print(format ++ "\n", args) catch os.abort();
143194 if (trace) |t| {
144 dumpStackTrace(t);
195 dumpStackTrace(t.*);
145196 }
146197 dumpCurrentStackTrace(first_trace_addr);
147198
......@@ -155,16 +206,15 @@ const WHITE = "\x1b[37;1m";
155206const DIM = "\x1b[2m";
156207const RESET = "\x1b[0m";
157208
158pub fn writeStackTrace(stack_trace: *const builtin.StackTrace, out_stream: var, allocator: *mem.Allocator, debug_info: *DebugInfo, tty_color: bool) !void {
159 var frame_index: usize = undefined;
160 var frames_left: usize = undefined;
161 if (stack_trace.index < stack_trace.instruction_addresses.len) {
162 frame_index = 0;
163 frames_left = stack_trace.index;
164 } else {
165 frame_index = (stack_trace.index + 1) % stack_trace.instruction_addresses.len;
166 frames_left = stack_trace.instruction_addresses.len;
167 }
209pub fn writeStackTrace(
210 stack_trace: builtin.StackTrace,
211 out_stream: var,
212 allocator: *mem.Allocator,
213 debug_info: *DebugInfo,
214 tty_color: bool,
215) !void {
216 var frame_index: usize = 0;
217 var frames_left: usize = stack_trace.index;
168218
169219 while (frames_left != 0) : ({
170220 frames_left -= 1;
std/special/bootstrap.zig+7-4
......@@ -23,8 +23,8 @@ nakedcc fn _start() noreturn {
2323 switch (builtin.arch) {
2424 builtin.Arch.x86_64 => {
2525 argc_ptr = asm ("lea (%%rsp), %[argc]"
26 : [argc] "=r" (-> [*]usize)
27 );
26 : [argc] "=r" (-> [*]usize)
27 );
2828 },
2929 builtin.Arch.i386 => {
3030 argc_ptr = asm ("lea (%%esp), %[argc]"
......@@ -123,7 +123,7 @@ inline fn callMain() u8 {
123123 std.debug.warn("error: {}\n", @errorName(err));
124124 if (builtin.os != builtin.Os.zen) {
125125 if (@errorReturnTrace()) |trace| {
126 std.debug.dumpStackTrace(trace);
126 std.debug.dumpStackTrace(trace.*);
127127 }
128128 }
129129 return 1;
......@@ -142,7 +142,10 @@ fn linuxInitializeThreadLocalStorage(at_phdr: usize, at_phnum: usize, at_phent:
142142 var phdr_addr = at_phdr;
143143 var n = at_phnum;
144144 var base: usize = 0;
145 while (n != 0) : ({n -= 1; phdr_addr += at_phent;}) {
145 while (n != 0) : ({
146 n -= 1;
147 phdr_addr += at_phent;
148 }) {
146149 const phdr = @intToPtr(*std.elf.Phdr, phdr_addr);
147150 // TODO look for PT_DYNAMIC when we have https://github.com/ziglang/zig/issues/1917
148151 switch (phdr.p_type) {