On 2020-03-17 9:51 a.m., Simon Marchi wrote: > Hi, > > I had to make a GDB fix related to Cygwin recently, so I tried to run some > tests > from the GDB testsuite on Cygwin. This is my first foray into Cygwin. > > The test I ran failed, because the GDB under test outputs what appears to be > control > sequences to clear the remaining characters of the line and go to the new > line. What's > surprising is that these control characters only start to appear when we use > the "run" > command of GDB, which makes GDB spawn the process to debug. > > The full test log is here: > > https://pastebin.com/raw/m6JYGRvs > > But here are a few lines around where it starts getting interesting: > > (gdb) break main > Breakpoint 1 at 0x1004012e3: file > /home/smarchi/src/binutils-gdb/gdb/testsuite/gdb.base/sizeof.c, line 101. > (gdb) run > Starting program: > /home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.base/sizeof/sizeof > [?25l[HType "apropos word" to search for commands related to > "word".[19X[19C > (gdb) set height 0[62X[62C > (gdb) set width 0[63X[63C > (gdb) dir[71X[71C > > The numbers match the number of characters left to the line, after what has > already been > output (for a total of 80). According to [1], the 'X' is "Erase Character" > and the 'C' is > "Cursor Forward". > > When the program starts, we also see one for "Text Cursor Enable Mode Hide". > > These control sequences are a bit problematic, because all the text that the > testsuite > is supposed to match is not matched, and the tests fail. > > It was suggested to me (by jturney on IRC) to use: > > export CYGWIN=disable_pcon > > To disable to use the new new Windows Pseudo Console thing. And indeed, it > makes the output > free of these escape sequences, and the test passes fine. > > Anybody can explain what is happening, and what we should do about it? > > Thanks, > > Simon > > [1] > https://docs.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences >
Oh well, I just saw this response from Ken earlier today (sorry about that, I'm not subscribed to the list): https://sourceware.org/pipermail/cygwin/2020-March/244091.html So I guess there's no explanation yet, just the workaround. Simon -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
