http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56891
Bug #: 56891
Summary: Bad static analysis on fread() gives spurious warning
on valid code
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: lto
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: gwo...@gmail.com
Created attachment 29838
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29838
Minimal tarball with makefile
The following code should read 17 bytes into a buffer of size 256.
But the link-time-optimiser assumes that the read size still has its (initial)
massive value, and gives an error
gcc-4.8, GNU/Linux, Ubuntu Lucid with PPA
gcc-4.8 -v gives:
COLLECT_GCC=gcc-4.8
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.8/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.8.0-2ubuntu2~10.04.1' --with-bugurl=file:///usr/share/doc/gcc-4.8/README.Bugs
--enable-languages=c,c++,go,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-4.8 --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--with-gxx-include-dir=/usr/include/c++/4.8 --libdir=/usr/lib --enable-nls
--enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes
--enable-gnu-unique-object --enable-plugin --with-system-zlib --enable-objc-gc
--disable-werror --with-arch-32=i586 --with-abi=m64
--with-multilib-list=m32,m64 --with-tune=generic --enable-checking=release
--build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.8.0 (Ubuntu/Linaro 4.8.0-2ubuntu2~10.04.1)
