title: linker claims library not found, strace shows it try to access valid path though
body: <p>I am trying to cross-compile something for Android, so I am using a separate toolchain.  There is a library that the linker is complaining it cannot find:</p>
  
  <pre><code>arm-eabi-gcc: fatal error: -fuse-linker-plugin, but liblto_plugin.so not found
  </code></pre>
  
  <p>The library definitely exists in this path:</p>
  
  <pre><code>$ ls -l /mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/libexec/gcc/arm-eabi/4.6.x-google
  total 70053
  -rwxr-xr-x 1 501 dialout 47040814 Oct  3 14:29 cc1
  -rwxr-xr-x 1 501 dialout 50903764 Oct  3 14:29 cc1plus
  -rwxr-xr-x 1 501 dialout   423914 Oct  3 14:29 collect2
  drwxr-xr-x 1 501 dialout      204 Oct  3 14:29 install-tools
  -rwxr-xr-x 1 501 dialout     1090 Oct  3 14:29 libfunction_reordering_plugin.la
  lrwxr-xr-x 1 501 dialout       38 Oct  3 14:29 libfunction_reordering_plugin.so -&gt; libfunction_reordering_plugin.so.0.0.0
  lrwxr-xr-x 1 501 dialout       38 Oct  3 14:29 libfunction_reordering_plugin.so.0 -&gt;  libfunction_reordering_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout    89427 Oct  3 14:29 libfunction_reordering_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout      994 Oct  3 14:29 liblto_plugin.la
  lrwxr-xr-x 1 501 dialout       22 Oct  3 14:29 liblto_plugin.so -&gt; liblto_plugin.so.0.0.0
  lrwxr-xr-x 1 501 dialout       22 Oct  3 14:29 liblto_plugin.so.0 -&gt; liblto_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout   238575 Oct  3 14:29 liblto_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout 44647203 Oct  3 14:29 lto1
  -rwxr-xr-x 1 501 dialout   114284 Oct  3 14:29 lto-wrapper
  </code></pre>
  
  <p>So, in my compile line I included "-L/mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/libexec/gcc/arm-eabi/4.6.x-google" and then specify "-lliblto_plugin" ... but I still continue to get this error.</p>
  
  <p>Here is my entire line and error:</p>
  
  <pre><code>arm-eabi-gcc -o test \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/../android-ndk-r8b-linux/platforms/android-14/arch-arm/usr/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/../ported-deps/jni/libgcrypt/src \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/../ported-deps/jni/libgpg-error/src \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/system/core/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/hardware/libhardware/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/hardware/ril/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/dalvik/libnativehelper/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/frameworks/base/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/external/skia/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/out/target/product/generic/obj/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libc/arch-arm/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libc/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libstdc++/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libc/kernel/common \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libc/kernel/arch-arm \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libm/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libm/include/arch/arm \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libthread_db/include \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libm/arm \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/bionic/libm \
  -I/mnt/hgfs/Documents/thesis/android-wmon/core/os/out/target/product/generic/obj/SHARED_LIBRARIES/libm_intermediates \
  -D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ -DANDROID -DSK_RELEASE -DNDEBUG \
  -include /mnt/hgfs/Documents/thesis/android-wmon/core/os/system/core/include/arch/linux-arm/AndroidConfig.h \
  -UDEBUG -march=armv5te -mtune=xscale -msoft-float -mthumb-interwork \
  -fpic -fno-exceptions -ffunction-sections -funwind-tables -fstack-protector -fmessage-length=0 \
  test.c \
  -Bdynamic -Wl,-T,/mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/arm-eabi/lib/ldscripts/armelf.x \
  -Wl,-dynamic-linker,/system/bin/linker -Wl,--gc-sections -Wl,-z,nocopyreloc \
  -Wl,--no-undefined -Wl,-rpath-link=/mnt/hgfs/Documents/thesis/android-wmon/core/os/../android-ndk-r8b-linux/platforms/android-14/arch-arm/usr/lib \
  -L/mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/libexec/gcc/arm-eabi/4.6.x-google \
  -L/mnt/hgfs/Documents/thesis/android-wmon/core/os/../android-ndk-r8b-linux/platforms/android-14/arch-arm/usr/lib \
  -nostdlib /mnt/hgfs/Documents/thesis/android-wmon/core/os/../android-ndk-r8b-linux/platforms/android-14/arch-arm/usr/lib/crtend_android.o \
  /mnt/hgfs/Documents/thesis/android-wmon/core/os/../android-ndk-r8b-linux/platforms/android-14/arch-arm/usr/lib/crtbegin_dynamic.o \
  /mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/lib/gcc/arm-eabi/4.6.x-google/libgcc.a \
  -lc -lliblto_plugin -lm
  arm-eabi-gcc: fatal error: -fuse-linker-plugin, but liblto_plugin.so not found
  </code></pre>
  
  <hr>
  
  <p>EDIT:  Running strace along with the compile, I see the accesses to read the shared library that fail:</p>
  
  <pre><code>access("/mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/../libexec/gcc/arm-eabi/4.6.x-google/liblto_plugin.so", R_OK) = -1 ENOENT (No such file or directory)
  access("/mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/../libexec/gcc/liblto_plugin.so", R_OK) = -1 ENOENT (No such file or directory)
  access("/mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/../lib/gcc/arm-eabi/4.6.x-google/../../../../arm-eabi/bin/arm-eabi/4.6.x-google/liblto_plugin.so", R_OK) = -1 ENOENT (No such file or directory)
  access("/mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/../lib/gcc/arm-eabi/4.6.x-google/../../../../arm-eabi/bin/liblto_plugin.so", R_OK) = -1 ENOENT (No such file or directory)
  </code></pre>
  
  <p>But interestingly, the first path that it tries does in fact exist, but it is a link:</p>
  
  <pre><code>$ file /mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/../libexec/gcc/arm-eabi/4.6.x-google/liblto_plugin.so 
  /mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/../libexec/gcc/arm-eabi/4.6.x-google/liblto_plugin.so: symbolic link to `liblto_plugin.so.0.0.0'
  </code></pre>
  
  <p>That link is also valid:  </p>
  
  <pre><code>    $ ls -l /mnt/hgfs/Documents/thesis/android-wmon/core/os/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/../libexec/gcc/arm-eabi/4.6.x-google/
  total 70053
  -rwxr-xr-x 1 501 dialout 47040814 Oct  3 14:29 cc1
  -rwxr-xr-x 1 501 dialout 50903764 Oct  3 14:29 cc1plus
  -rwxr-xr-x 1 501 dialout   423914 Oct  3 14:29 collect2
  drwxr-xr-x 1 501 dialout      204 Oct  3 14:29 install-tools
  -rwxr-xr-x 1 501 dialout     1090 Oct  3 14:29 libfunction_reordering_plugin.la
  lrwxr-xr-x 1 501 dialout       38 Oct  3 14:29 libfunction_reordering_plugin.so -&gt; libfunction_reordering_plugin.so.0.0.0
  lrwxr-xr-x 1 501 dialout       38 Oct  3 14:29 libfunction_reordering_plugin.so.0 -&gt; libfunction_reordering_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout    89427 Oct  3 14:29 libfunction_reordering_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout      994 Oct  3 14:29 liblto_plugin.la
  lrwxr-xr-x 1 501 dialout       22 Oct  3 14:29 liblto_plugin.so -&gt; liblto_plugin.so.0.0.0
  lrwxr-xr-x 1 501 dialout       22 Oct  3 14:29 liblto_plugin.so.0 -&gt; liblto_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout   238575 Oct  3 14:29 liblto_plugin.so.0.0.0
  -rwxr-xr-x 1 501 dialout 44647203 Oct  3 14:29 lto1
  -rwxr-xr-x 1 501 dialout   114284 Oct  3 14:29 lto-wrapper
  </code></pre>
  
  <hr>
  
  <p>ANOTHER EDIT:  If I go in to the directory containing the shared library and remove the link from liblto_plugin.so to liblto_plugin.so.0.0.0 and then "cp liblto_plugin.so.0.0.0 liblto_plugin.so" then it links properly and my program compiles.  Why is it broken when this file is a link?  (sorry, using "link" to refer to two different things here).</p>