Re: shadow variables - pg15 edition

Hi,

On 2022-10-06 10:21:41 +1300, David Rowley wrote:
> Also pushed. (Thanks for saving me on that one.)

Your commit message said the last shadowed variable. But building with
-Wshadow=compatible-local triggers a bunch of warnings for me (see trimmed at
the end). Looks like it "only" fixed it for src/, without optional
dependencies like gssapi and python.

I think we should add -Wshadow=compatible-local to our sets of warning flags
after fixing those.

[237/1827 42 12%] Compiling C object src/interfaces/libpq/libpq.a.p/fe-secure-gssapi.c.o
../../../../home/andres/src/postgresql/src/interfaces/libpq/fe-secure-gssapi.c: In function ‘pg_GSS_write’:
../../../../home/andres/src/postgresql/src/interfaces/libpq/fe-secure-gssapi.c:138:41: warning: declaration of ‘ret’ shadows a previous local [-Wshadow=compatible-local]
138 | ssize_t ret;
| ^~~
../../../../home/andres/src/postgresql/src/interfaces/libpq/fe-secure-gssapi.c:92:25: note: shadowed declaration is here
92 | ssize_t ret = -1;
| ^~~

[1283/1827 42 70%] Compiling C object src/pl/plpython/plpython3.so.p/plpy_cursorobject.c.o
In file included from ../../../../home/andres/src/postgresql/src/include/postgres.h:48,
from ../../../../home/andres/src/postgresql/src/pl/plpython/plpy_cursorobject.c:7:
../../../../home/andres/src/postgresql/src/pl/plpython/plpy_cursorobject.c: In function ‘PLy_cursor_plan’:
../../../../home/andres/src/postgresql/src/include/utils/elog.h:325:29: warning: declaration of ‘_save_exception_stack’ shadows a previous local [-Wshadow=compatible-local]
325 | sigjmp_buf *_save_exception_stack##__VA_ARGS__ = PG_exception_stack; \
| ^~~~~~~~~~~~~~~~~~~~~
...

[1289/1827 42 70%] Compiling C object src/pl/plpython/plpython3.so.p/plpy_exec.c.o
../../../../home/andres/src/postgresql/src/pl/plpython/plpy_exec.c: In function ‘PLy_exec_trigger’:
../../../../home/andres/src/postgresql/src/pl/plpython/plpy_exec.c:378:46: warning: declaration of ‘tdata’ shadows a previous local [-Wshadow=compatible-local]
378 | TriggerData *tdata = (TriggerData *) fcinfo->context;
| ^~~~~
../../../../home/andres/src/postgresql/src/pl/plpython/plpy_exec.c:310:22: note: shadowed declaration is here
310 | TriggerData *tdata;
| ^~~~~

[1291/1827 42 70%] Compiling C object src/pl/plpython/plpython3.so.p/plpy_spi.c.o
In file included from ../../../../home/andres/src/postgresql/src/include/postgres.h:48,
from ../../../../home/andres/src/postgresql/src/pl/plpython/plpy_spi.c:7:
../../../../home/andres/src/postgresql/src/pl/plpython/plpy_spi.c: In function ‘PLy_spi_execute_plan’:
../../../../home/andres/src/postgresql/src/include/utils/elog.h:325:29: warning: declaration of ‘_save_exception_stack’ shadows a previous local [-Wshadow=compatible-local]
325 | sigjmp_buf *_save_exception_stack##__VA_ARGS__ = PG_exception_stack; \
| ^~~~~~~~~~~~~~~~~~~~~

[1344/1827 42 73%] Compiling C object contrib/bloom/bloom.so.p/blinsert.c.o
../../../../home/andres/src/postgresql/contrib/bloom/blinsert.c: In function ‘blinsert’:
../../../../home/andres/src/postgresql/contrib/bloom/blinsert.c:235:33: warning: declaration of ‘page’ shadows a previous local [-Wshadow=compatible-local]
235 | Page page;
| ^~~~
../../../../home/andres/src/postgresql/contrib/bloom/blinsert.c:210:25: note: shadowed declaration is here
210 | Page page,
| ^~~~

[1415/1827 42 77%] Compiling C object contrib/file_fdw/file_fdw.so.p/file_fdw.c.o
../../../../home/andres/src/postgresql/contrib/file_fdw/file_fdw.c: In function ‘get_file_fdw_attribute_options’:
../../../../home/andres/src/postgresql/contrib/file_fdw/file_fdw.c:453:29: warning: declaration of ‘options’ shadows a previous local [-Wshadow=compatible-local]
453 | List *options;
| ^~~~~~~
../../../../home/andres/src/postgresql/contrib/file_fdw/file_fdw.c:443:21: note: shadowed declaration is here
443 | List *options = NIL;
| ^~~~~~~

[1441/1827 42 78%] Compiling C object contrib/hstore/hstore.so.p/hstore_io.c.o
In file included from ../../../../home/andres/src/postgresql/contrib/hstore/hstore_io.c:12:
../../../../home/andres/src/postgresql/contrib/hstore/hstore_io.c: In function ‘hstorePairs’:
../../../../home/andres/src/postgresql/contrib/hstore/hstore.h:131:21: warning: declaration of ‘buflen’ shadows a parameter [-Wshadow=compatible-local]
131 | int buflen = (ptr_) - (buf_); \
| ^~~~~~
../../../../home/andres/src/postgresql/contrib/hstore/hstore_io.c:411:9: note: in expansion of macro ‘HS_FINALIZE’
411 | HS_FINALIZE(out, pcount, buf, ptr);
| ^~~~~~~~~~~
../../../../home/andres/src/postgresql/contrib/hstore/hstore_io.c:388:47: note: shadowed declaration is here
388 | hstorePairs(Pairs *pairs, int32 pcount, int32 buflen)
| ~~~~~~^~~~~~

[1564/1827 42 85%] Compiling C object contrib/postgres_fdw/postgres_fdw.so.p/deparse.c.o
../../../../home/andres/src/postgresql/contrib/postgres_fdw/deparse.c: In function ‘foreign_expr_walker’:
../../../../home/andres/src/postgresql/contrib/postgres_fdw/deparse.c:946:53: warning: declaration of ‘lc’ shadows a previous local [-Wshadow=compatible-local]
946 | ListCell *lc;
| ^~
../../../../home/andres/src/postgresql/contrib/postgres_fdw/deparse.c:904:45: note: shadowed declaration is here
904 | ListCell *lc;
| ^~

[1575/1827 38 86%] Compiling C object src/test/modules/test_integerset/test_integerset.so.p/test_integerset.c.o
../../../../home/andres/src/postgresql/src/test/modules/test_integerset/test_integerset.c: In function ‘test_huge_distances’:
../../../../home/andres/src/postgresql/src/test/modules/test_integerset/test_integerset.c:588:33: warning: declaration of ‘x’ shadows a previous local [-Wshadow=compatible-local]
588 | uint64 x = values[i];
| ^
../../../../home/andres/src/postgresql/src/test/modules/test_integerset/test_integerset.c:526:25: note: shadowed declaration is here
526 | uint64 x;
| ^

[1633/1827 3 89%] Compiling C object contrib/postgres_fdw/postgres_fdw.so.p/postgres_fdw.c.o
../../../../home/andres/src/postgresql/contrib/postgres_fdw/postgres_fdw.c: In function ‘postgresGetForeignPlan’:
../../../../home/andres/src/postgresql/contrib/postgres_fdw/postgres_fdw.c:1344:37: warning: declaration of ‘lc’ shadows a previous local [-Wshadow=compatible-local]
1344 | ListCell *lc;
| ^~
../../../../home/andres/src/postgresql/contrib/postgres_fdw/postgres_fdw.c:1238:21: note: shadowed declaration is here
1238 | ListCell *lc;
| ^~

Greetings,

Andres Freund