Hi,
with the following patch I suggest to add a diagnostic for extra
semicolons after in-class member function definitions:
struct A
{
A() {};
void foo() {};
friend void bar() {};
};
Although they are allowed in the C++ standard, people (including me)
often like to get rid of them for stylistic/consistency reasons.
In fact clang has a warning -Wextra-semi for this.
Also in GCC (almost exactly 10 years ago) there was a patch
https://gcc.gnu.org/ml/gcc-cvs/2007-03/msg00841.html
to issue a pedwarn (which had to be reverted as GCC would reject valid
code because of the pedwarn).
Instead of using pewarn the patch below adds a new warning (named like
clang's) to warn about these redundant semicolons.
Btw, clang's warning message "extra ';' after member function definition"
is slightly incorrect because it is also emitted for friend functions
which are not member-functions. That's why I suggest a different wording:
Wextra-semi.C:3:9: warning: extra ';' after in-class function definition
[-Wextra-semi]
A() {};
^
Wextra-semi.C:4:16: warning: extra ';' after in-class function definition
[-Wextra-semi]
void foo() {};
^
Wextra-semi.C:5:23: warning: extra ';' after in-class function definition
[-Wextra-semi]
friend void bar() {};
^
Bootstrapped and regtested on x86_64-pc-linux-gnu.
OK for stage 1, once GCC 7 has branched?
Regards,
Volker
2017-04-07 Volker Reichelt <v.reich...@netcologne.de>
* c.opt (Wextra-semi): New C++ warning flag.
Index: gcc/c-family/c.opt
===================================================================
--- gcc/c-family/c.opt (revision 246752)
+++ gcc/c-family/c.opt (working copy)
@@ -504,6 +504,10 @@
C ObjC C++ ObjC++ Warning
; in common.opt
+Wextra-semi
+C++ Var(warn_extra_semi) Warning
+Warn about semicolon after in-class function definition.
+
Wfloat-conversion
C ObjC C++ ObjC++ Var(warn_float_conversion) Warning LangEnabledBy(C ObjC C++
ObjC++,Wconversion)
Warn for implicit type conversions that cause loss of floating point precision.
2017-04-07 Volker Reichelt <v.reich...@netcologne.de>
* parser.c (cp_parser_member_declaration): Add warning for
extra semicolon after in-class function definition.
Index: gcc/cp/parser.c
===================================================================
--- gcc/cp/parser.c (revision 246752)
+++ gcc/cp/parser.c (working copy)
@@ -23386,7 +23386,11 @@
token = cp_lexer_peek_token (parser->lexer);
/* If the next token is a semicolon, consume it. */
if (token->type == CPP_SEMICOLON)
- cp_lexer_consume_token (parser->lexer);
+ {
+ cp_lexer_consume_token (parser->lexer);
+ warning (OPT_Wextra_semi, "extra %<;%> "
+ "after in-class function definition");
+ }
goto out;
}
else
2017-04-07 Volker Reichelt <v.reich...@netcologne.de>
* g++.dg/warn/Wextra-semi.C: New test.
Index: gcc/testsuite/g++.dg/warn/Wextra-semi.C
===================================================================
--- gcc/testsuite/g++.dg/warn/Wextra-semi.C 2017-04-07
+++ gcc/testsuite/g++.dg/warn/Wextra-semi.C 2017-04-07
@@ -0,0 +1,8 @@
+// { dg-options "-Wextra-semi" }
+
+struct A
+{
+ A() {}; // { dg-warning "after in-class function definition" }
+ void foo() {}; // { dg-warning "after in-class function definition" }
+ friend void bar() {}; // { dg-warning "after in-class function
definition" }
+};
===================================================================
