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the goal of the patch is to fix the following problem: |
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|
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"Dan Nicholson" <dbn.lists@gmail.com> writes: |
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|
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[...] |
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|
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> And now I've come upon this old thread: |
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> |
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> http://rpm5.org/community/rpm-devel/1554.html |
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> |
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> This is definitely the problem. When --as-needed is used, libc is |
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> bound first to tmire, causing regcomp and friends to be resolved |
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> through libc rather than libpcreposix. |
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|
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the symbol conflict is a mess. pcreposix better be fixed |
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(http://rpm5.org/community/rpm-devel/1562.html) |
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|
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it's hard to beat libc... here is what happens: |
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|
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% echo 'int f() { regcomp(); }' > liba.c |
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% gcc -shared -o liba.so liba.c -lpcreposix |
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% ldd liba.so |
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libpcreposix.so.0 => /usr/lib/libpcreposix.so.0 (0xb7f76000) |
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libc.so.6 => /lib/i686/libc.so.6 (0xb7e28000) |
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libpcre.so.0 => /lib/libpcre.so.0 (0xb7e00000) |
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% gcc -shared -o liba_.so liba.so |
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% LD_LIBRARY_PATH=`pwd` ldd liba_.so |
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liba.so => /tmp/liba.so (0xb7f44000) |
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libc.so.6 => /lib/i686/libc.so.6 (0xb7de2000) |
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libpcreposix.so.0 => /usr/lib/libpcreposix.so.0 (0xb7de0000) |
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libpcre.so.0 => /lib/libpcre.so.0 (0xb7db8000) |
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|
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one can see -lc has been added. confirmed by: |
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|
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% gcc -nostdlib -shared -o liba_.so liba.so |
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% LD_LIBRARY_PATH=`pwd` ldd liba_.so |
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liba.so => /tmp/liba.so (0xb7f19000) |
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libpcreposix.so.0 => /usr/lib/libpcreposix.so.0 (0xb7f03000) |
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libc.so.6 => /lib/i686/libc.so.6 (0xb7db5000) |
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libpcre.so.0 => /lib/libpcre.so.0 (0xb7d8d000) |
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|
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but using -nostdlib is harder when building a binary... hence the need |
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to force -lpcreposix at each linking steps: |
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|
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% gcc -shared -o liba_.so liba.so -lpcreposix |
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% LD_LIBRARY_PATH=`pwd` ldd liba_.so |
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liba.so => /tmp/liba.so (0xb7f9f000) |
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libpcreposix.so.0 => /usr/lib/libpcreposix.so.0 (0xb7f89000) |
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libc.so.6 => /lib/i686/libc.so.6 (0xb7e3b000) |
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libpcre.so.0 => /lib/libpcre.so.0 (0xb7e13000) |
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|
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|
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which defeats the idea of DSO which should handle their deps themselves. |
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and such hacks do not play well with --as-needed: |
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|
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export LD_LIBRARY_PATH=/tmp |
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cd /tmp |
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echo 'int f() { printf("fa "); }' > liba.c |
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echo 'int f() { printf("fb "); }' > libb.c |
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echo 'int g() { }' >> libb.c |
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echo 'int h() { f(); g(); }' > libx.c |
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echo 'main() { h(); g(); printf("\n"); }' > t.c |
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gcc -o liba.so -shared liba.c |
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gcc -o libb.so -shared libb.c |
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gcc -o libx.so -shared libx.c -L. -la -lb |
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gcc t.c -L. -lx ; ./a.out # fb |
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gcc t.c -L. -lx -la; ./a.out # fa |
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gcc -Wl,--as-needed t.c -L. -lx -la; ./a.out # fb |
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|
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|
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i wonder if ld could have a warning to detect about multiple symbols |
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in DSO and so tell about possible issues with --as-needed. |
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|
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|
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diff --git a/configure.ac b/configure.ac |
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index 38d1dba..d423f0f 100644 |
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--- a/configure.ac |
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+++ b/configure.ac |
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@@ -20,7 +20,7 @@ m4_define(pcre_date, [2015-04-28]) |
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m4_define(libpcre_version, [3:5:2]) |
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m4_define(libpcre16_version, [2:5:2]) |
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m4_define(libpcre32_version, [0:5:0]) |
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-m4_define(libpcreposix_version, [0:3:0]) |
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+m4_define(libpcreposix_version, [1:0:0]) |
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m4_define(libpcrecpp_version, [0:1:0]) |
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|
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AC_PREREQ(2.57) |
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diff --git a/pcreposix.h b/pcreposix.h |
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index 6424a74..b869da5 100644 |
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--- a/pcreposix.h |
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+++ b/pcreposix.h |
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@@ -132,15 +132,19 @@ file. */ |
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#endif |
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|
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/* The functions */ |
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- |
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-PCREPOSIX_EXP_DECL int regcomp(regex_t *, const char *, int); |
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-PCREPOSIX_EXP_DECL int regexec(const regex_t *, const char *, size_t, |
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+PCREPOSIX_EXP_DECL int pcreposix_regcomp(regex_t *, const char *, int); |
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+PCREPOSIX_EXP_DECL int pcreposix_regexec(const regex_t *, const char *, size_t, |
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regmatch_t *, int); |
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-PCREPOSIX_EXP_DECL size_t regerror(int, const regex_t *, char *, size_t); |
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-PCREPOSIX_EXP_DECL void regfree(regex_t *); |
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+PCREPOSIX_EXP_DECL size_t pcreposix_regerror(int, const regex_t *, char *, size_t); |
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+PCREPOSIX_EXP_DECL void pcreposix_regfree(regex_t *); |
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|
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#ifdef __cplusplus |
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} /* extern "C" */ |
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#endif |
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|
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+#define regcomp pcreposix_regcomp |
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+#define regexec pcreposix_regexec |
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+#define regerror pcreposix_regerror |
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+#define regfree pcreposix_regfree |
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+ |
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#endif /* End of pcreposix.h */ |
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