[Bug c/44056] New: plugin compile error: rtl.def uses "const" keyword because of "CONST" defined to "const" in include/ansidecl.h

["crquan at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

Tried native compile gcc-4.50 on both x86_64-linux and i686-linux, and install
into separate directory, it can compile small plugin demo, and demo plugin also
worked well;

but while writing a useful gcc plugin with FOR_EACH_LOOP from cfgloop.h, it
exited with error:

gcc -I.
-I/opt/gcc-4.5.0/usr/bin/../lib/gcc/x86_64-pc-linux-gnu/4.5.0/plugin/include
-fPIC -c -o sensor_code_generators/univariate_polynomial.o
sensor_code_generators/univariate_polynomial.c
In file included from
/opt/gcc-4.5.0/usr/bin/../lib/gcc/x86_64-pc-linux-gnu/4.5.0/plugin/include/rtl.h:48:0,
                 from
/opt/gcc-4.5.0/usr/bin/../lib/gcc/x86_64-pc-linux-gnu/4.5.0/plugin/include/cfgloop.h:26,
                 from sensor_code_generators/univariate_polynomial.c:15:
/opt/gcc-4.5.0/usr/bin/../lib/gcc/x86_64-pc-linux-gnu/4.5.0/plugin/include/rtl.def:336:1:
error: expected identifier before 'const'
In file included from
/opt/gcc-4.5.0/usr/bin/../lib/gcc/x86_64-pc-linux-gnu/4.5.0/plugin/include/cfgloop.h:26:0,
                 from sensor_code_generators/univariate_polynomial.c:15:
/opt/gcc-4.5.0/usr/bin/../lib/gcc/x86_64-pc-linux-gnu/4.5.0/plugin/include/rtl.h:98:39:
error: 'LAST_AND_UNUSED_RTX_CODE' undeclared here (not in a function)
sensor_code_generators/univariate_polynomial.c:92:1: warning: useless storage
class specifier in empty declaration
make: *** [sensor_code_generators/univariate_polynomial.o] Error 1

The very first error is "expected identifier before 'const'", due to "const"
keyword used as enumeration, in rtl.def,

Further speaking, CONST is defined to const in include/ansidecl.h, only when
without IN_GCC defined,

But if I use -DIN_GCC to compile my own plugin, it produced other more random
errors,

So I think the problem is because rtl.def ansidecl.h conflicts,

Searched one mail archive on this Feb 2010 is related, but the author didn't
tell how to "reorder",

http://www.mail-archive.com/gcc@gcc.gnu.org/msg49585.html


BTW: There may be other gcc-4.5.0 new plugin system bugs, I personally suggest
a new bugzilla component "gcc-plugin" for this category of bugs;


-- 
           Summary: plugin compile error: rtl.def uses "const" keyword
                    because of "CONST" defined to "const" in
                    include/ansidecl.h
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: crquan at gmail dot com
  GCC host triplet: native x86_64-linux and i686-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44056