Make failmalloc disable itself on program exit.

Something in the Travis build environment has changed recently to cause
failmalloc runs to crash while exiting due to a NULL pointer dereference
in the coverage writing code. This fix causes failmalloc to
automatically disable itself once main() exits so subsequent memory
requests always succeed. Since the application (and library) have no
control over what happens during exit cleanup anyway, this does not
affect its functionality.

diff --git a/.travis.yml b/.travis.yml
index be28883..3ed8491 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -150,7 +150,11 @@ install:
         curl -fsSORL --retry 8 https://download.savannah.nongnu.org/releases/failmalloc/failmalloc-1.0.tar.gz
         tar xaf failmalloc-1.0.tar.gz
         cd failmalloc-1.0
+        # Fix compiling with modern glibc
         sed -i -e 's/\(__malloc_initialize_hook\)/volatile \1/' failmalloc.c
+        # Disable failmalloc on program exit so system code can run unimpeded
+        sed -i -e '/failmalloc_init/,${/failmalloc_install/aatexit(failmalloc_uninstall);
+        }' failmalloc.c
         ./configure --prefix="$HOME/failmalloc" --disable-dependency-tracking
         make
         make install
@@ -172,11 +176,11 @@ script:
   - if [ "$CONFIG" = "musl" ] ; then CFLAGS='-Wall -Wextra -O3'; export CC=musl-gcc; CONFIGURE_OPTS='--disable-shared'; fi
   - if [ "$CONFIG" = "sanitize" ] ; then CFLAGS='-g -Wall -Wextra -fsanitize=address -fsanitize=undefined -fsanitize-address-use-after-scope'; export CC=clang-8; export ASAN_OPTIONS=strict_string_checks=1:detect_stack_use_after_return=1:check_initialization_order=1:strict_init_order=1:detect_leaks=1; fi
   - if [ "$CONFIG" = "coverage" ] ; then cd "$HOME"/libexif-testsuite; CFLAGS=--coverage; CONFIGURE_OPTS="LDFLAGS=--coverage --with-failmalloc=$HOME/failmalloc/lib" ; fi
-  - ./configure --prefix="$HOME"/install --disable-dependency-tracking CFLAGS="$CFLAGS" $CONFIGURE_OPTS || { tail -300 config.log; false; }
+  - ./configure --prefix="$HOME"/install --disable-dependency-tracking CFLAGS="$CFLAGS" $CONFIGURE_OPTS || { tail -n 300 config.log; false; }
 
   - make V=1
   # Skip tests when cross compiling.
-  - if [ "$CONFIG" != "arm-cross" ] ; then make V=1 check || { tail -300 test*/test-suite.log; false; }; fi
+  - if [ "$CONFIG" != "arm-cross" ] ; then make V=1 check || { tail -n 300 test*/test-suite.log src/libexif/test*/test-suite.log; false; }; fi
   - make V=1 install
 
   - if [ "$CONFIG" = "coverage" ] ; then cd "$TRAVIS_BUILD_DIR"; fi