On Wed, Jan 18, 2023 at 12:45:50AM +0000, Bjarni Ingi Gislason wrote: > Package: byacc > Version: byacc - 2.0 20221229 > Severity: normal > > Dear Maintainer, > > * What led up to the situation? > > Compiling groff
(in a quick check, I compiled the version from 2022/12/28
on my Debian/oldstable without seeing this problem - but I see
the issue is compiler options).
> ####
>
> output.c: putl_code(fp, "#if !(defined(yylex) || defined(YYSTATE))\n");
>
> "yylex" is a name of a function but "#... defined(...)" applies to
> macros not functions(?).
That's intentional (not a bug). It's done to allow changing the function
signature -- but not if there's already a macro to confuse things.
Here's more context:
/* Parameters sent to lex. */
#ifdef YYLEX_PARAM
# define YYLEX_DECL() yylex(void *YYLEX_PARAM)
# define YYLEX yylex(YYLEX_PARAM)
#else
# define YYLEX_DECL() yylex(void)
# define YYLEX yylex()
#endif
#if !(defined(yylex) || defined(YYSTATE))
int YYLEX_DECL();
#endif
Changing that YYSTATE to YYLEX will turn off the declaration.
YYSTATE is a lex symbol (#define'd), so it seemed a better choice than
the flex-specific FLEX_SCANNER symbol which Guy Harris used in the first
version of this ifdef.
The intent here is to not use the declaration if the lex/flex code is
inserted before that point (reducing redefinition problems).
> ####
>
> When compiling, a warning is issued:
>
> CXX src/preproc/eqn/eqn-eqn.o
> src/preproc/eqn/eqn.cpp:73:23: warning: redundant redeclaration of 'int
> yylex()' in same scope [-Wredundant-decls]
> 73 | # define YYLEX_DECL() yylex(void)
> | ^~~~~
yes - that's a problem. There's been no universally-guaranteed prototype
for yylex, so applications add one. (There was some update on the Austin
review a couple of years ago, but the recommendation from that would run
into the same problem -- and it introduced other problems).
For this case, I could add a third symbol, which would "only" be set by
the caller (not a lex/flex symbol that one might trip over).
> src/preproc/eqn/eqn.cpp:78:5: note: in expansion of macro 'YYLEX_DECL'
> 78 | int YYLEX_DECL();
> | ^~~~~~~~~~
> ../src/preproc/eqn/eqn.ypp:31:5: note: previous declaration of 'int
> yylex()'
> 31 | int yylex(void);
> | ^~~~~
> CXXLD eqn
>
> ####
>
> When I change "yylex" to "YYLEX" in the "putl_code(...)" line there
> is no warning.
>
> -- System Information:
> Debian Release: bookworm/sid
> APT prefers testing
> APT policy: (500, 'testing')
> Architecture: amd64 (x86_64)
>
> Kernel: Linux 6.0.12-1 (SMP w/2 CPU threads; PREEMPT)
> Kernel taint flags: TAINT_WARN
> Locale: LANG=is_IS.iso88591, LC_CTYPE=is_IS.iso88591 (charmap=ISO-8859-1),
> LANGUAGE not set
> Shell: /bin/sh linked to /usr/bin/dash
> Init: sysvinit (via /sbin/init)
>
> Versions of packages byacc depends on:
> ii libc6 2.36-8
>
> byacc recommends no packages.
>
> byacc suggests no packages.
--
Thomas E. Dickey <dic...@invisible-island.net>
https://invisible-island.net
signature.asc
Description: PGP signature
