[ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[JeanHeyd Meneide]

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Dear GCC,

     This patch adds macros to the general preprocessor that allow
users to understand what the execution and wide execution charsets
are, which are used for "bark" and L"meow" literals in C-family
languages.

     The goal of this is to enable individuals in capable languages
like C and C++ to determine the encoding of string literals and,
hopefully, transcode those literals to other encodings. For example,
data stored in `char[]` on an IBM machine with EBCDIC can be
(losslessly, or with a compile-time warning) transcoded to UTF-8 at
constant-expression time in C++ with this patch, without having to use
a series of complicated architecture and platform definitions to
figure out what the encoding of string literals and wide character
literals might be.

     The names are meaningful because they are tied directly to iconv,
which means there is a strong reference between the name and the code
that encodes/decodes a proper sequence. Therefore, we just present the
names.

     Does this sound useful?

Sincerely,
JeanHeyd

Patch notes: the strings passed to the charset creation routines are
all static and/or allocated far at the beginning of the program and
never deallocated until the end of the invocation, so it seems safe to
just store a normal pointer to it.

2020-10-08  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>

        * gcc/c-family/c-cppbuiltin.c: Add predefined macro
definitions for charsets
        * gcc/doc/cpp.texi: Document new predefined macro.
        * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c (new):
          New test for macro definitions to always exist.
        * libcpp/include/cpplib.h: Add functions declarations for
          retrieving charset names
        * libcpp/directives.c: Add function definitions to retrieve charset
          names.
        * libcpp/internal.h: Add to/from name preservations

[-- Attachment #2: encoding_names.patch.txt --]
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diff --git a/gcc/c-family/c-cppbuiltin.c b/gcc/c-family/c-cppbuiltin.c
index 74ecca8de8e..8de25786592 100644
--- a/gcc/c-family/c-cppbuiltin.c
+++ b/gcc/c-family/c-cppbuiltin.c
@@ -866,6 +866,13 @@ c_cpp_builtins (cpp_reader *pfile)
 
   define_language_independent_builtin_macros (pfile);
 
+  /* encoding definitions used by users and libraries  */
+  builtin_define_with_value ("__GNUC_EXECUTION_CHARSET_NAME",
+    cpp_get_narrow_charset_name (pfile), 1);
+  builtin_define_with_value ("__GNUC_WIDE_EXECUTION_CHARSET_NAME",
+    cpp_get_wide_charset_name (pfile), 1);
+
+
   if (c_dialect_cxx ())
   {
     int major;
diff --git a/gcc/doc/cpp.texi b/gcc/doc/cpp.texi
index 33f876ab706..55fa5739812 100644
--- a/gcc/doc/cpp.texi
+++ b/gcc/doc/cpp.texi
@@ -2451,6 +2451,13 @@ features are supported by GCC.
 @item __NO_MATH_ERRNO__
 This macro is defined if @option{-fno-math-errno} is used, or enabled
 by another option such as @option{-ffast-math} or by default.
+
+@item __GNUC_EXECUTION_CHARSET_NAME
+@itemx __GNUC_WIDE_EXECUTION_CHARSET_NAME
+These macros are defined to the name of the narrow and wide compile-time
+execution character set used.  It directly reflects the name passed to
+the options @option{-fexec-charset} and @option{-fwide-exec-charset},
+or the defaults documented for those options.  @xref{Invocation}.
 @end table
 
 @node System-specific Predefined Macros
diff --git a/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c b/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c
new file mode 100644
index 00000000000..0f55e6915f4
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c
@@ -0,0 +1,10 @@
+/*
+   { dg-do compile }
+ */
+
+#if !defined(__GNUC_EXECUTION_CHARSET_NAME)
+#error "Required implementation macro for compile-time charset name is not present"
+#endif
+#if !defined(__GNUC_WIDE_EXECUTION_CHARSET_NAME)
+#error "Required implementation macro for wide compile-time charset name is not present"
+#endif
diff --git a/libcpp/charset.c b/libcpp/charset.c
index 28b81c9c864..3e5578b1390 100644
--- a/libcpp/charset.c
+++ b/libcpp/charset.c
@@ -638,6 +638,9 @@ init_iconv_desc (cpp_reader *pfile, const char *to, const char *from)
   char *pair;
   size_t i;
 
+  ret.to = to;
+  ret.from = from;
+
   if (!strcasecmp (to, from))
     {
       ret.func = convert_no_conversion;
diff --git a/libcpp/directives.c b/libcpp/directives.c
index f59718708e4..ad540872581 100644
--- a/libcpp/directives.c
+++ b/libcpp/directives.c
@@ -2571,6 +2571,20 @@ cpp_set_callbacks (cpp_reader *pfile, cpp_callbacks *cb)
   pfile->cb = *cb;
 }
 
+/* The narrow character set identifier.  */
+const char *
+cpp_get_narrow_charset_name (cpp_reader *pfile)
+{
+  return pfile->narrow_cset_desc.to;
+}
+
+/* The wide character set identifier.  */
+const char *
+cpp_get_wide_charset_name (cpp_reader *pfile)
+{
+  return pfile->wide_cset_desc.to;
+}
+
 /* The dependencies structure.  (Creates one if it hasn't already been.)  */
 class mkdeps *
 cpp_get_deps (cpp_reader *pfile)
diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index 8e398863cf6..69a5042d0bf 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -971,6 +971,11 @@ extern cpp_callbacks *cpp_get_callbacks (cpp_reader *) ATTRIBUTE_PURE;
 extern void cpp_set_callbacks (cpp_reader *, cpp_callbacks *);
 extern class mkdeps *cpp_get_deps (cpp_reader *) ATTRIBUTE_PURE;
 
+/* Call these to get name data about the various compile-time
+   charsets.  */
+extern const char *cpp_get_narrow_charset_name (cpp_reader *) ATTRIBUTE_PURE;
+extern const char *cpp_get_wide_charset_name (cpp_reader *) ATTRIBUTE_PURE;
+
 /* This function reads the file, but does not start preprocessing.  It
    returns the name of the original file; this is the same as the
    input file, except for preprocessed input.  This will generate at
diff --git a/libcpp/internal.h b/libcpp/internal.h
index 4bafe1cf353..0a85766ff41 100644
--- a/libcpp/internal.h
+++ b/libcpp/internal.h
@@ -48,6 +48,8 @@ struct cset_converter
   convert_f func;
   iconv_t cd;
   int width;
+  const char* from;
+  const char* to;
 };
 
 #define BITS_PER_CPPCHAR_T (CHAR_BIT * sizeof (cppchar_t))

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[Joseph Myers]

On Thu, 8 Oct 2020, JeanHeyd Meneide via Gcc-patches wrote:

>         * gcc/doc/cpp.texi: Document new predefined macro.

This documentation doesn't seem sufficient to use the macros.  Do they 
expand to (narrow) string literals?  To an unquoted sequence of 
characters?  I think from the implementation that the answer is strings 
(so, in particular, not usable for testing anything in #if conditionals), 
but the documentation ought to say so.  The test ought to verify the form 
of the expansion as well (even if it can't do anything useful at execution 
time, because if you make the macros reflect the command-line options they 
are character set names that are meaningful on the host, and any 
conversion functionality on the target may not use the same names as the 
host).

-- 
Joseph S. Myers
joseph@codesourcery.com

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[JeanHeyd Meneide]

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Dear Joseph,

On Thu, Oct 8, 2020 at 1:36 PM Joseph Myers <joseph@codesourcery.com> wrote:
>
> This documentation doesn't seem sufficient to use the macros.  Do they
> expand to (narrow) string literals?  To an unquoted sequence of
> characters?  I think from the implementation that the answer is strings
> (so, in particular, not usable for testing anything in #if conditionals),
> but the documentation ought to say so.  The test ought to verify the form
> of the expansion as well (even if it can't do anything useful at execution
> time, because if you make the macros reflect the command-line options they
> are character set names that are meaningful on the host, and any
> conversion functionality on the target may not use the same names as the
> host).

     You're right; sorry about that, I should have been more thorough!
I thought about adding a test to check the name itself (e.g, for
"UTF-8"), but that might make tests fail on platforms where the
default SOURCE_CHARSET from the dev files is not, in fact, UTF-8. I
could also try to pass some options but then I'd have to guarantee
that the encoding was available on all testable platforms, too...!

    In the end, for the tests, I just initialize two "const char[]"
directly from the macro expansions to make sure we are getting
strings. It seeeeeems to work okay. Attached is the revised patch with
better docs and test!

Sincerely,
JeanHeyd

2020-10-08  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>

        * gcc/c-family/c-cppbuiltin.c: Add predefined macro
definitions for charsets
        * gcc/doc/cpp.texi: Document new predefined macro.
        * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c (new):
          New test for macro definitions to always exist.
        * libcpp/include/cpplib.h: Add functions declarations for
          retrieving charset names
        * libcpp/directives.c: Add function definitions to retrieve charset
          names.
        * libcpp/internal.h: Add to/from name preservations

[-- Attachment #2: encoding_names.patch.txt --]
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diff --git a/gcc/c-family/c-cppbuiltin.c b/gcc/c-family/c-cppbuiltin.c
index 74ecca8de8e..8de25786592 100644
--- a/gcc/c-family/c-cppbuiltin.c
+++ b/gcc/c-family/c-cppbuiltin.c
@@ -866,6 +866,13 @@ c_cpp_builtins (cpp_reader *pfile)
 
   define_language_independent_builtin_macros (pfile);
 
+  /* encoding definitions used by users and libraries  */
+  builtin_define_with_value ("__GNUC_EXECUTION_CHARSET_NAME",
+    cpp_get_narrow_charset_name (pfile), 1);
+  builtin_define_with_value ("__GNUC_WIDE_EXECUTION_CHARSET_NAME",
+    cpp_get_wide_charset_name (pfile), 1);
+
+
   if (c_dialect_cxx ())
   {
     int major;
diff --git a/gcc/doc/cpp.texi b/gcc/doc/cpp.texi
index 33f876ab706..90f1162add1 100644
--- a/gcc/doc/cpp.texi
+++ b/gcc/doc/cpp.texi
@@ -2451,6 +2451,15 @@ features are supported by GCC.
 @item __NO_MATH_ERRNO__
 This macro is defined if @option{-fno-math-errno} is used, or enabled
 by another option such as @option{-ffast-math} or by default.
+
+@item __GNUC_EXECUTION_CHARSET_NAME
+@itemx __GNUC_WIDE_EXECUTION_CHARSET_NAME
+These macros are defined to expand to a narrow string literal of
+the name of the narrow and wide compile-time execution character
+set used.  It directly reflects the name passed to the options
+@option{-fexec-charset} and @option{-fwide-exec-charset}, or the defaults
+documented for those options (that is, it can expand to something like 
+@code{"UTF-8"}).  @xref{Invocation}.
 @end table
 
 @node System-specific Predefined Macros
diff --git a/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c b/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c
new file mode 100644
index 00000000000..d5440f8a61e
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c
@@ -0,0 +1,13 @@
+/*
+   { dg-do compile }
+ */
+
+#if !defined(__GNUC_EXECUTION_CHARSET_NAME)
+#error "Required implementation macro for comple-time charset name is not present"
+#endif
+#if !defined(__GNUC_WIDE_EXECUTION_CHARSET_NAME)
+#error "Required implementation macro for wide comple-time charset name is not present"
+#endif
+
+const char narrow_name[] = __GNUC_EXECUTION_CHARSET_NAME;
+const char wide_name[] = __GNUC_WIDE_EXECUTION_CHARSET_NAME;
diff --git a/libcpp/charset.c b/libcpp/charset.c
index 28b81c9c864..3e5578b1390 100644
--- a/libcpp/charset.c
+++ b/libcpp/charset.c
@@ -638,6 +638,9 @@ init_iconv_desc (cpp_reader *pfile, const char *to, const char *from)
   char *pair;
   size_t i;
 
+  ret.to = to;
+  ret.from = from;
+
   if (!strcasecmp (to, from))
     {
       ret.func = convert_no_conversion;
diff --git a/libcpp/directives.c b/libcpp/directives.c
index f59718708e4..ad540872581 100644
--- a/libcpp/directives.c
+++ b/libcpp/directives.c
@@ -2571,6 +2571,20 @@ cpp_set_callbacks (cpp_reader *pfile, cpp_callbacks *cb)
   pfile->cb = *cb;
 }
 
+/* The narrow character set identifier.  */
+const char *
+cpp_get_narrow_charset_name (cpp_reader *pfile)
+{
+  return pfile->narrow_cset_desc.to;
+}
+
+/* The wide character set identifier.  */
+const char *
+cpp_get_wide_charset_name (cpp_reader *pfile)
+{
+  return pfile->wide_cset_desc.to;
+}
+
 /* The dependencies structure.  (Creates one if it hasn't already been.)  */
 class mkdeps *
 cpp_get_deps (cpp_reader *pfile)
diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index 8e398863cf6..69a5042d0bf 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -971,6 +971,11 @@ extern cpp_callbacks *cpp_get_callbacks (cpp_reader *) ATTRIBUTE_PURE;
 extern void cpp_set_callbacks (cpp_reader *, cpp_callbacks *);
 extern class mkdeps *cpp_get_deps (cpp_reader *) ATTRIBUTE_PURE;
 
+/* Call these to get name data about the various compile-time
+   charsets.  */
+extern const char *cpp_get_narrow_charset_name (cpp_reader *) ATTRIBUTE_PURE;
+extern const char *cpp_get_wide_charset_name (cpp_reader *) ATTRIBUTE_PURE;
+
 /* This function reads the file, but does not start preprocessing.  It
    returns the name of the original file; this is the same as the
    input file, except for preprocessed input.  This will generate at
diff --git a/libcpp/internal.h b/libcpp/internal.h
index b728df74562..a6402d77ced 100644
--- a/libcpp/internal.h
+++ b/libcpp/internal.h
@@ -48,6 +48,8 @@ struct cset_converter
   convert_f func;
   iconv_t cd;
   int width;
+  const char* from;
+  const char* to;
 };
 
 #define BITS_PER_CPPCHAR_T (CHAR_BIT * sizeof (cppchar_t))

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[Bernhard Reutner-Fischer]

On 8 October 2020 23:39:15 CEST, JeanHeyd Meneide via Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
>Dear Joseph,
>
>On Thu, Oct 8, 2020 at 1:36 PM Joseph Myers <joseph@codesourcery.com>
>wrote:
>>
>> This documentation doesn't seem sufficient to use the macros.  Do
>they
>> expand to (narrow) string literals?  To an unquoted sequence of
>> characters?  I think from the implementation that the answer is
>strings
>> (so, in particular, not usable for testing anything in #if
>conditionals),
>> but the documentation ought to say so.  The test ought to verify the
>form
>> of the expansion as well (even if it can't do anything useful at
>execution
>> time, because if you make the macros reflect the command-line options
>they
>> are character set names that are meaningful on the host, and any
>> conversion functionality on the target may not use the same names as
>the
>> host).
>
>     You're right; sorry about that, I should have been more thorough!
>I thought about adding a test to check the name itself (e.g, for
>"UTF-8"), but that might make tests fail on platforms where the
>default SOURCE_CHARSET from the dev files is not, in fact, UTF-8. I
>could also try to pass some options but then I'd have to guarantee
>that the encoding was available on all testable platforms, too...!
>
>    In the end, for the tests, I just initialize two "const char[]"
>directly from the macro expansions to make sure we are getting
>strings. It seeeeeems to work okay. Attached is the revised patch with
>better docs and test!

Typo:  comple-time

>2020-10-08  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>
>
>        * gcc/c-family/c-cppbuiltin.c: Add predefined macro
>definitions for charsets

I think you should put the macro names in braces after the filename and drop the trailing "for charsets".

>        * gcc/doc/cpp.texi: Document new predefined macro.
>    * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c (new):

I think you should drop "(new)" above.
thanks,

>          New test for macro definitions to always exist.
>        * libcpp/include/cpplib.h: Add functions declarations for
>          retrieving charset names
>    * libcpp/directives.c: Add function definitions to retrieve charset
>          names.
>        * libcpp/internal.h: Add to/from name preservations

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[JeanHeyd Meneide]

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Hello,

> Typo:  comple-time
>
> >2020-10-08  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>
> >
> >        * gcc/c-family/c-cppbuiltin.c: Add predefined macro
> >definitions for charsets
>
> I think you should put the macro names in braces after the filename and drop the trailing "for charsets".

     Can do!

>
> >        * gcc/doc/cpp.texi: Document new predefined macro.
> >    * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c (new):
>
> I think you should drop "(new)" above.
> thanks,

     I saw that in previous changelogs, but I can change it! Fixed up
the typos, too.

Sincerely,
JeanHeyd

2020-10-09  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>

        * gcc/c-family/c-cppbuiltin.c: Add predefined
          {__GNUC_EXECUTION_CHARSET_NAME} and
          {__GNUC_WIDE_EXECUTION_CHARSET_NAME} macros
        * gcc/doc/cpp.texi: Document above new predefined macros
        * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c:
          New test for macro definitions to always exist and be strings
        * libcpp/include/cpplib.h: Add functions declarations for
          retrieving charset names
        * libcpp/directives.c: Add function definitions to retrieve charset
          names
        * libcpp/internal.h: Add to/from name preservations

[-- Attachment #2: encoding_names.patch.txt --]
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diff --git a/gcc/c-family/c-cppbuiltin.c b/gcc/c-family/c-cppbuiltin.c
index 74ecca8de8e..8de25786592 100644
--- a/gcc/c-family/c-cppbuiltin.c
+++ b/gcc/c-family/c-cppbuiltin.c
@@ -866,6 +866,13 @@ c_cpp_builtins (cpp_reader *pfile)
 
   define_language_independent_builtin_macros (pfile);
 
+  /* encoding definitions used by users and libraries  */
+  builtin_define_with_value ("__GNUC_EXECUTION_CHARSET_NAME",
+    cpp_get_narrow_charset_name (pfile), 1);
+  builtin_define_with_value ("__GNUC_WIDE_EXECUTION_CHARSET_NAME",
+    cpp_get_wide_charset_name (pfile), 1);
+
+
   if (c_dialect_cxx ())
   {
     int major;
diff --git a/gcc/doc/cpp.texi b/gcc/doc/cpp.texi
index 33f876ab706..90f1162add1 100644
--- a/gcc/doc/cpp.texi
+++ b/gcc/doc/cpp.texi
@@ -2451,6 +2451,15 @@ features are supported by GCC.
 @item __NO_MATH_ERRNO__
 This macro is defined if @option{-fno-math-errno} is used, or enabled
 by another option such as @option{-ffast-math} or by default.
+
+@item __GNUC_EXECUTION_CHARSET_NAME
+@itemx __GNUC_WIDE_EXECUTION_CHARSET_NAME
+These macros are defined to expand to a narrow string literal of
+the name of the narrow and wide compile-time execution character
+set used.  It directly reflects the name passed to the options
+@option{-fexec-charset} and @option{-fwide-exec-charset}, or the defaults
+documented for those options (that is, it can expand to something like 
+@code{"UTF-8"}).  @xref{Invocation}.
 @end table
 
 @node System-specific Predefined Macros
diff --git a/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c b/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c
new file mode 100644
index 00000000000..d5440f8a61e
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c
@@ -0,0 +1,13 @@
+/*
+   { dg-do compile }
+ */
+
+#if !defined(__GNUC_EXECUTION_CHARSET_NAME)
+#error "Required implementation macro for compile-time charset name is not present"
+#endif
+#if !defined(__GNUC_WIDE_EXECUTION_CHARSET_NAME)
+#error "Required implementation macro for wide compile-time charset name is not present"
+#endif
+
+const char narrow_name[] = __GNUC_EXECUTION_CHARSET_NAME;
+const char wide_name[] = __GNUC_WIDE_EXECUTION_CHARSET_NAME;
diff --git a/libcpp/charset.c b/libcpp/charset.c
index 28b81c9c864..3e5578b1390 100644
--- a/libcpp/charset.c
+++ b/libcpp/charset.c
@@ -638,6 +638,9 @@ init_iconv_desc (cpp_reader *pfile, const char *to, const char *from)
   char *pair;
   size_t i;
 
+  ret.to = to;
+  ret.from = from;
+
   if (!strcasecmp (to, from))
     {
       ret.func = convert_no_conversion;
diff --git a/libcpp/directives.c b/libcpp/directives.c
index f59718708e4..ad540872581 100644
--- a/libcpp/directives.c
+++ b/libcpp/directives.c
@@ -2571,6 +2571,20 @@ cpp_set_callbacks (cpp_reader *pfile, cpp_callbacks *cb)
   pfile->cb = *cb;
 }
 
+/* The narrow character set identifier.  */
+const char *
+cpp_get_narrow_charset_name (cpp_reader *pfile)
+{
+  return pfile->narrow_cset_desc.to;
+}
+
+/* The wide character set identifier.  */
+const char *
+cpp_get_wide_charset_name (cpp_reader *pfile)
+{
+  return pfile->wide_cset_desc.to;
+}
+
 /* The dependencies structure.  (Creates one if it hasn't already been.)  */
 class mkdeps *
 cpp_get_deps (cpp_reader *pfile)
diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index 8e398863cf6..69a5042d0bf 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -971,6 +971,11 @@ extern cpp_callbacks *cpp_get_callbacks (cpp_reader *) ATTRIBUTE_PURE;
 extern void cpp_set_callbacks (cpp_reader *, cpp_callbacks *);
 extern class mkdeps *cpp_get_deps (cpp_reader *) ATTRIBUTE_PURE;
 
+/* Call these to get name data about the various compile-time
+   charsets.  */
+extern const char *cpp_get_narrow_charset_name (cpp_reader *) ATTRIBUTE_PURE;
+extern const char *cpp_get_wide_charset_name (cpp_reader *) ATTRIBUTE_PURE;
+
 /* This function reads the file, but does not start preprocessing.  It
    returns the name of the original file; this is the same as the
    input file, except for preprocessed input.  This will generate at
diff --git a/libcpp/internal.h b/libcpp/internal.h
index b728df74562..a6402d77ced 100644
--- a/libcpp/internal.h
+++ b/libcpp/internal.h
@@ -48,6 +48,8 @@ struct cset_converter
   convert_f func;
   iconv_t cd;
   int width;
+  const char* from;
+  const char* to;
 };
 
 #define BITS_PER_CPPCHAR_T (CHAR_BIT * sizeof (cppchar_t))

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[JeanHeyd Meneide]

(Very very gentle ping, just to make sure it's still on anyone's radar...!)

On Fri, Oct 9, 2020 at 8:39 AM JeanHeyd Meneide <phdofthehouse@gmail.com> wrote:
>
> Hello,
>
> > Typo:  comple-time
> >
> > >2020-10-08  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>
> > >
> > >        * gcc/c-family/c-cppbuiltin.c: Add predefined macro
> > >definitions for charsets
> >
> > I think you should put the macro names in braces after the filename and drop the trailing "for charsets".
>
>      Can do!
>
> >
> > >        * gcc/doc/cpp.texi: Document new predefined macro.
> > >    * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c (new):
> >
> > I think you should drop "(new)" above.
> > thanks,
>
>      I saw that in previous changelogs, but I can change it! Fixed up
> the typos, too.
>
> Sincerely,
> JeanHeyd
>
> 2020-10-09  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>
>
>         * gcc/c-family/c-cppbuiltin.c: Add predefined
>           {__GNUC_EXECUTION_CHARSET_NAME} and
>           {__GNUC_WIDE_EXECUTION_CHARSET_NAME} macros
>         * gcc/doc/cpp.texi: Document above new predefined macros
>         * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c:
>           New test for macro definitions to always exist and be strings
>         * libcpp/include/cpplib.h: Add functions declarations for
>           retrieving charset names
>         * libcpp/directives.c: Add function definitions to retrieve charset
>           names
>         * libcpp/internal.h: Add to/from name preservations

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[Jeff Law]

On 10/9/20 6:39 AM, JeanHeyd Meneide via Gcc-patches wrote:
> Hello,
>
>> Typo:  comple-time
>>
>>> 2020-10-08  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>
>>>
>>>        * gcc/c-family/c-cppbuiltin.c: Add predefined macro
>>> definitions for charsets
>> I think you should put the macro names in braces after the filename and drop the trailing "for charsets".
>      Can do!
>
>>>        * gcc/doc/cpp.texi: Document new predefined macro.
>>>    * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c (new):
>> I think you should drop "(new)" above.
>> thanks,
>      I saw that in previous changelogs, but I can change it! Fixed up
> the typos, too.
>
> Sincerely,
> JeanHeyd
>
> 2020-10-09  JeanHeyd "ThePhD" Meneide  <phdofthehouse@gmail.com>
>
>         * gcc/c-family/c-cppbuiltin.c: Add predefined
>           {__GNUC_EXECUTION_CHARSET_NAME} and
>           {__GNUC_WIDE_EXECUTION_CHARSET_NAME} macros
>         * gcc/doc/cpp.texi: Document above new predefined macros
>         * gcc/testsuite/c-c++-common/cpp/wide-narrow-predef-macros.c:
>           New test for macro definitions to always exist and be strings
>         * libcpp/include/cpplib.h: Add functions declarations for
>           retrieving charset names
>         * libcpp/directives.c: Add function definitions to retrieve charset
>           names
>         * libcpp/internal.h: Add to/from name preservations
>
> encoding_names.patch.txt
>

[ ... ]
> diff --git a/libcpp/charset.c b/libcpp/charset.c
> index 28b81c9c864..3e5578b1390 100644
> --- a/libcpp/charset.c
> +++ b/libcpp/charset.c
> @@ -638,6 +638,9 @@ init_iconv_desc (cpp_reader *pfile, const char *to, const char *from)
>    char *pair;
>    size_t i;
>  
> +  ret.to = to;
> +  ret.from = from;
> +
AFAICT ret.from is never used.  Is there a reason why you're saving it?


You use a getter function to retrieve the value of ret.to, which is
fine.  Is there a specific reason why you're not using a setter function
to save the value?

Otherwise I think this is basically ready to be included.

jeff

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[JeanHeyd Meneide]

Dear Jeff,

On Mon, Nov 23, 2020 at 3:02 PM Jeff Law <law@redhat.com> wrote:
>
> You use a getter function to retrieve the value of ret.to, which is
> fine.  Is there a specific reason why you're not using a setter function
> to save the value?

     I did this because I have access to ret.to in the libcpp
functions! Outside, the structure of that type is unknown and only a
pointer, so it needs the getter function.

Sincerely,
JeanHeyd

Re: [ Preprocessor ] [ Common ] Feature: Macros for identifying the wide and narrow execution string literal encoding

[Jeff Law]

On 11/23/20 1:40 PM, JeanHeyd Meneide wrote:
> Dear Jeff,
>
> On Mon, Nov 23, 2020 at 3:02 PM Jeff Law <law@redhat.com> wrote:
>> You use a getter function to retrieve the value of ret.to, which is
>> fine.  Is there a specific reason why you're not using a setter function
>> to save the value?
>      I did this because I have access to ret.to in the libcpp
> functions! Outside, the structure of that type is unknown and only a
> pointer, so it needs the getter function.
Thanks.  I've fixed up the ChangeLog entry and pushed the patch to the
trunk.

Jeff