Re: ALTER TABLE lock downgrades have broken pg_upgrade

Stephen Frost wrote:

> One other point is that pg_dump goes quite a bit farther back than just
> what we currently support (or at least, it tries to).  I think that,
> generally, that's a good thing, but it does mean we have a lot of cases
> that don't get tested nearly as much...
> 
> I was able to get back to 7.4 up and running without too much trouble,
> but even that doesn't cover all the cases we have in pg_dump.  I'm not
> sure if we want to define a "we will support pg_dump back to X" cut-off
> or if we want to try and get older versions to run on modern systems,
> but it's definitely worth pointing out that we're trying to support much
> farther back than what is currently supported in pg_dump today.

Yeah.  Trying to compile old stuff with current tools (Debian jessie):

7.0's configure does not recognize my system:

checking host system type... Invalid configuration `x86_64-unknown-linux-gnu': machine `x86_64-unknown' not recognized

7.1's configure fails for accept() detection:

checking types of arguments for accept()... configure: error: could not determine argument types

7.2's configure works, but apparently it failed to find flex:

make[3]: Entering directory '/home/alvherre/Code/pgsql/source/throwaway/src/backend/bootstrap'
***
ERROR: `flex' is missing on your system. It is needed to create the
file `bootscanner.c'. You can either get flex from a GNU mirror site
or download an official distribution of PostgreSQL, which contains
pre-packaged flex output.
***
Makefile:60: recipe for target 'bootscanner.c' failed
make[3]: *** [bootscanner.c] Error 1


7.3 fails in ecpg preprocessor:

make[4]: Entering directory '/home/alvherre/Code/pgsql/source/throwaway/src/interfaces/ecpg/preproc'
make -C ../../../../src/port all
make[5]: Entering directory '/home/alvherre/Code/pgsql/source/throwaway/src/port'
make[5]: Nothing to be done for 'all'.
make[5]: Leaving directory '/home/alvherre/Code/pgsql/source/throwaway/src/port'
gcc -O2 -fno-strict-aliasing -Wall -Wmissing-prototypes -Wmissing-declarations -Wno-error -I./../include -I.
-I../../../../src/include -DMAJOR_VERSION=2 -DMINOR_VERSION=10 -DPATCHLEVEL=0
-DINCLUDE_PATH=\"/usr/local/pgsql/include\"  -c -o preproc.o preproc.c
 
In file included from preproc.y:5571:0:
pgc.c:170:18: error: conflicting types for ‘yyleng’extern yy_size_t yyleng;                 ^
In file included from preproc.y:7:0:
extern.h:32:4: note: previous declaration of ‘yyleng’ was here   yyleng;   ^
In file included from preproc.y:5571:0:
pgc.c:304:11: error: conflicting types for ‘yyleng’yy_size_t yyleng;          ^
In file included from preproc.y:7:0:
extern.h:32:4: note: previous declaration of ‘yyleng’ was here   yyleng;   ^
In file included from preproc.y:5571:0:
pgc.c:2723:16: warning: ‘input’ defined but not used [-Wunused-function]    static int input  (void)               ^
<builtin>: recipe for target 'preproc.o' failed
make[4]: *** [preproc.o] Error 1


7.4 seems to work fine.  I suppose it should be fine to remove pg_dump's
support for pre-7.3; people wanting to upgrade from before 7.3 (if any)
could use 9.6's pg_dump as an intermediate jump.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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