[Bug c++/80955] Macros expanded in definition of user-defined literals

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

--- Comment #8 from Jonathan Wakely  ---
Also the new testcase for this bug has undefined behaviour. _ID is a reserved
name so the program cannot use it to define a macro or a UDL.

[Bug c++/80955] Macros expanded in definition of user-defined literals

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

--- Comment #7 from Jonathan Wakely  ---
Moved to PR 84517

[Bug c++/80955] Macros expanded in definition of user-defined literals

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

--- Comment #6 from Jonathan Wakely  ---
Testing this:

--- a/libcpp/lex.c
+++ b/libcpp/lex.c
@@ -1903,7 +1903,7 @@ lex_raw_string (cpp_reader *pfile, cpp_token *token,
const uchar *base,
 literal thus breaking the program.
 Try to identify macros with is_macro. A warning is issued.
 The macro name should not start with '_' for this warning. */
-  if ((*cur != '_') && is_macro (pfile, cur))
+  if ((*cur != '_' || cur[1] == '_') && is_macro (pfile, cur))
{
  /* Raise a warning, but do not consume subsequent tokens.  */
  if (CPP_OPTION (pfile, warn_literal_suffix) &&
!pfile->state.skipping)
@@ -2034,7 +2034,7 @@ lex_string (cpp_reader *pfile, cpp_token *token, const
uchar *base)
 literal thus breaking the program.
 Try to identify macros with is_macro. A warning is issued.
 The macro name should not start with '_' for this warning. */
-  if ((*cur != '_') && is_macro (pfile, cur))
+  if ((*cur != '_' || cur[1] == '_') && is_macro (pfile, cur))
{
  /* Raise a warning, but do not consume subsequent tokens.  */
  if (CPP_OPTION (pfile, warn_literal_suffix) &&
!pfile->state.skipping)

[Bug c++/80955] Macros expanded in definition of user-defined literals

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

--- Comment #5 from Jonathan Wakely  ---
Is there a way to check if it's a pre-defined macro?

Or just change the condition to allow starting with two underscores, but not
allow starting with one (since user-defined UDLs must start with a single
underscore, and must not start with two).

[Bug c++/80955] Macros expanded in definition of user-defined literals

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

--- Comment #4 from Jonathan Wakely  ---
This causes a regression for:

const char* err() { return "Error in "__FILE__; }


file.cc: In function ‘const char* err()’:
file.cc:1:28: error: unable to find string literal operator
‘operator""__FILE__’ with ‘const char [10]’, ‘long unsigned int’ arguments
 const char* err() { return "Error in "__FILE__; }
^~~

With GCC 7 this gave a warning about not finding a literal operator, and then
continued as the author intended, i.e. concatenating the two strings.

[Bug c++/80955] Macros expanded in definition of user-defined literals

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

Paolo Carlini  changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 Resolution|--- |FIXED
   Target Milestone|--- |8.0

--- Comment #3 from Paolo Carlini  ---
Fixed.

[Bug c++/80955] Macros expanded in definition of user-defined literals

[paolo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

--- Comment #2 from paolo at gcc dot gnu.org  ---
Author: paolo
Date: Mon Nov  6 10:33:41 2017
New Revision: 254443

URL: https://gcc.gnu.org/viewcvs?rev=254443=gcc=rev
Log:
/libcpp
2017-11-06  Mukesh Kapoor  

PR c++/80955
* lex.c (lex_string): When checking for a valid macro for the
warning related to -Wliteral-suffix (CPP_W_LITERAL_SUFFIX),
check that the macro name does not start with an underscore
before calling is_macro().

/gcc/testsuite
2017-11-06  Mukesh Kapoor  

PR c++/80955
* g++.dg/cpp0x/udlit-macros.C: New.

Added:
trunk/gcc/testsuite/g++.dg/cpp0x/udlit-macros.C
Modified:
trunk/gcc/testsuite/ChangeLog
trunk/libcpp/ChangeLog
trunk/libcpp/lex.c

[Bug c++/80955] Macros expanded in definition of user-defined literals

[mukesh.kapoor at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

Mukesh Kapoor  changed:

   What|Removed |Added

 CC||mukesh.kapoor at oracle dot com

--- Comment #1 from Mukesh Kapoor  ---
Incorrect parsing of string.
I am working on this.

[Bug c++/80955] Macros expanded in definition of user-defined literals

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80955

Jonathan Wakely  changed:

   What|Removed |Added

 Status|UNCONFIRMED |NEW
   Last reconfirmed||2017-06-02
 Ever confirmed|0   |1