Merge pull request #4319 from Rocknest/windows-traces

Bring windows segfault handler on par with linux 

1 files changed, 31 insertions, 6 deletions

diff --git a/lib/std/debug.zig b/lib/std/debug.zig
index a5fd1a4712..28340fede2 100644
--- a/lib/std/debug.zig
+++ b/lib/std/debug.zig
@@ -131,6 +131,7 @@ pub fn dumpStackTraceFromBase(bp: usize, ip: usize) void {
     const tty_config = detectTTYConfig();
     printSourceAtAddress(debug_info, stderr, ip, tty_config) catch return;
     const first_return_address = @intToPtr(*const usize, bp + @sizeOf(usize)).*;
+    if (first_return_address == 0) return; // The whole call stack may be optimized out
     printSourceAtAddress(debug_info, stderr, first_return_address - 1, tty_config) catch return;
     var it = StackIterator{
         .first_addr = null,
@@ -325,6 +326,7 @@ pub const StackIterator = struct {
         }
 
         const return_address = @intToPtr(*const usize, self.fp - fp_adjust_factor + @sizeOf(usize)).*;
+        if (return_address == 0) return null;
         return return_address;
     }
 };
@@ -470,7 +472,7 @@ fn printSourceAtAddressWindows(
                                 line_index += @sizeOf(pdb.LineNumberEntry);
 
                                 const vaddr_start = frag_vaddr_start + line_num_entry.Offset;
-                                if (relative_address <= vaddr_start) {
+                                if (relative_address < vaddr_start) {
                                     break;
                                 }
                             }
@@ -2309,16 +2311,39 @@ fn handleSegfaultLinux(sig: i32, info: *const os.siginfo_t, ctx_ptr: *const c_vo
 }
 
 fn handleSegfaultWindows(info: *windows.EXCEPTION_POINTERS) callconv(.Stdcall) c_long {
-    const exception_address = @ptrToInt(info.ExceptionRecord.ExceptionAddress);
     switch (info.ExceptionRecord.ExceptionCode) {
-        windows.EXCEPTION_DATATYPE_MISALIGNMENT => panicExtra(null, exception_address, "Unaligned Memory Access", .{}),
-        windows.EXCEPTION_ACCESS_VIOLATION => panicExtra(null, exception_address, "Segmentation fault at address 0x{x}", .{info.ExceptionRecord.ExceptionInformation[1]}),
-        windows.EXCEPTION_ILLEGAL_INSTRUCTION => panicExtra(null, exception_address, "Illegal Instruction", .{}),
-        windows.EXCEPTION_STACK_OVERFLOW => panicExtra(null, exception_address, "Stack Overflow", .{}),
+        windows.EXCEPTION_DATATYPE_MISALIGNMENT => handleSegfaultWindowsExtra(info, 0, "Unaligned Memory Access"),
+        windows.EXCEPTION_ACCESS_VIOLATION => handleSegfaultWindowsExtra(info, 1, null),
+        windows.EXCEPTION_ILLEGAL_INSTRUCTION => handleSegfaultWindowsExtra(info, 2, null),
+        windows.EXCEPTION_STACK_OVERFLOW => handleSegfaultWindowsExtra(info, 0, "Stack Overflow"),
         else => return windows.EXCEPTION_CONTINUE_SEARCH,
     }
 }
 
+// zig won't let me use an anon enum here https://github.com/ziglang/zig/issues/3707
+fn handleSegfaultWindowsExtra(info: *windows.EXCEPTION_POINTERS, comptime msg: u8, comptime format: ?[]const u8) noreturn {
+    const exception_address = @ptrToInt(info.ExceptionRecord.ExceptionAddress);
+    if (@hasDecl(windows, "CONTEXT")) {
+        const regs = info.ContextRecord.getRegs();
+        switch (msg) {
+            0 => std.debug.warn("{}\n", .{format.?}),
+            1 => std.debug.warn("Segmentation fault at address 0x{x}\n", .{info.ExceptionRecord.ExceptionInformation[1]}),
+            2 => std.debug.warn("Illegal instruction at address 0x{x}\n", .{regs.ip}),
+            else => unreachable,
+        }
+
+        dumpStackTraceFromBase(regs.bp, regs.ip);
+        os.abort();
+    } else {
+        switch (msg) {
+            0 => panicExtra(null, exception_address, format.?, .{}),
+            1 => panicExtra(null, exception_address, "Segmentation fault at address 0x{x}", .{info.ExceptionRecord.ExceptionInformation[1]}),
+            2 => panicExtra(null, exception_address, "Illegal Instruction", .{}),
+            else => unreachable,
+        }
+    }
+}
+
 pub fn dumpStackPointerAddr(prefix: []const u8) void {
     const sp = asm (""
         : [argc] "={rsp}" (-> usize)