On Mon, Dec 31, 2018 at 11:24 PM Donald Dong <xdong(at)csumb(dot)edu> wrote:
>
> Hi,
>
> In src/test/example, the implicit make rules produce errors:
>
> make -C ../../../src/backend generated-headers
> make[1]: Entering directory '/home/ddong/postgresql/bld/src/backend'
> make -C catalog distprep generated-header-symlinks
> make[2]: Entering directory '/home/ddong/postgresql/bld/src/backend/catalog'
> make[2]: Nothing to be done for 'distprep'.
> make[2]: Nothing to be done for 'generated-header-symlinks'.
> make[2]: Leaving directory '/home/ddong/postgresql/bld/src/backend/catalog'
> make -C utils distprep generated-header-symlinks
> make[2]: Entering directory '/home/ddong/postgresql/bld/src/backend/utils'
> make[2]: Nothing to be done for 'distprep'.
> make[2]: Nothing to be done for 'generated-header-symlinks'.
> make[2]: Leaving directory '/home/ddong/postgresql/bld/src/backend/utils'
> make[1]: Leaving directory '/home/ddong/postgresql/bld/src/backend'
> gcc -Wall -Wmissing-prototypes -Wpointer-arith
> -Wdeclaration-after-statement -Werror=vla -Wendif-labels
> -Wmissing-format-attribute -Wformat-security -fno-strict-aliasing
> -fwrapv -fexcess-precision=standard -Wno-format-truncation -O2
> -I/home/ddong/postgresql/bld/../src/interfaces/libpq
> -I../../../src/include -I/home/ddong/postgresql/bld/../src/include
> -D_GNU_SOURCE -c -o testlibpq.o
> /home/ddong/postgresql/bld/../src/test/examples/testlibpq.c
> gcc -L../../../src/port -L../../../src/common -L../../../src/common
> -lpgcommon -L../../../src/port -lpgport
> -L../../../src/interfaces/libpq -lpq -Wl,--as-needed
> -Wl,-rpath,'/usr/local/pgsql/lib',--enable-new-dtags testlibpq.o -o
> testlibpq
> testlibpq.o: In function `exit_nicely':
> testlibpq.c:(.text.unlikely+0x5): undefined reference to `PQfinish'
> testlibpq.o: In function `main':
> testlibpq.c:(.text.startup+0x22): undefined reference to `PQconnectdb'
> testlibpq.c:(.text.startup+0x2d): undefined reference to `PQstatus'
> testlibpq.c:(.text.startup+0x44): undefined reference to `PQexec’
> …
>
> I think the -lpq flag does not have any effects in the middle of the
> arguments. It works if move the flag to the end:
>
> gcc -L../../../src/port -L../../../src/common -L../../../src/common
> -lpgcommon -L../../../src/port -lpgport
> -L../../../src/interfaces/libpq -Wl,--as-needed
> -Wl,-rpath,'/usr/local/pgsql/lib',--enable-new-dtags testlibpq.o -o
> testlibpq -lpq
>
> So I added an explicit rule to rearrange the flags:
>
> gcc testlibpq.o -o testlibpq -L../../../src/port -L../../../src/common
> -L../../../src/common -lpgcommon -L../../../src/port -lpgport
> -L../../../src/interfaces/libpq -lpq -Wl,--as-needed
> -Wl,-rpath,'/usr/local/pgsql/lib',--enable-new-dtags
>
> Then the make command works as expected. This is my first time writing
> a patch. Please let me know what you think!
>
> Thank you,
> Happy new year!
> Donald Dong
--
Donald Dong