git: 4bddff0833d3 - main - libdtrace: Work around a warning from flex

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=4bddff0833d3efee77a099b3ef447fbae1e63d21

commit 4bddff0833d3efee77a099b3ef447fbae1e63d21
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2024-06-01 15:16:26 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2024-06-01 15:16:26 +0000

    libdtrace: Work around a warning from flex
    
    When compiling dt_lex.l, flex produces warnings of the form:
    
      dt_lex.l:413: warning, trailing context made variable due to preceding '|' action
      dt_lex.l:412: warning, dangerous trailing context
      dt_lex.l:412: warning, dangerous trailing context
    
    Here, trailing context refers to the use of "$", which expands to "/\n".
    
    The meaning behind these warnings is described in the first two
    paragraphs of the flex manual's DEFICIENCIES/BUGS section:
    
      Some trailing context patterns cannot be properly matched and generate
      warning messages ("dangerous trailing context").  These are patterns
      where the ending of the first part of the rule matches the beginning of
      the second part, such as "zx*/xy*", where the 'x*' matches the 'x' at
      the beginning of the trailing context.  (Note that the POSIX draft
      states that the text matched by such patterns is undefined.)
    
      For some trailing context rules, parts which are actually fixed-length
      are not recognized as such, leading to the above mentioned performance
      loss.  In particular, parts using '|' or {n} (such as "foo{3}") are
      always considered variable-length.
    
    Here, the warnings appear to be bogus in this case.  The lexer has no
    problem matching either of the referenced patterns, e.g.,
    
      printf("foobar
    
    or
    
      # 1 "asdfasdf
    
    Introduce a small amount of code duplication to silence the warning.
    
    MFC after:      2 weeks
---
 cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l
index d50369bb57c9..756a48b9c45f 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l
@@ -407,7 +407,7 @@ if (yypcb->pcb_token != 0) {
 
 <S0>{RGX_FP}	yyerror("floating-point constants are not permitted\n");
 
-<S0>\"{RGX_STR}$ |
+<S0>\"{RGX_STR}$ xyerror(D_STR_NL, "newline encountered in string literal");
 <S3>\"{RGX_STR}$ xyerror(D_STR_NL, "newline encountered in string literal");
 
 <S0>\"{RGX_STR}\" |