RHBA-2009:1376 - Bug Fix Advisory

Topic

A gcc update that resolves several GFortran compiler bugs (along with
several other bugs) is now available.

Description

The gcc packages include C, C++, Java, Fortran, Objective C, and Ada 95 GNU
compilers, along with related support libraries.

This update applies the following bug fixes:

• 64-bit multiplication by constant on the x86 platform caused unexpected

aborts when compiling code that used 'unsigned long long' variables. This
was because the compiler did not check whether CONST_DOUBLE_LOW was
positive when multiplying constants. With this update, the compiler now
check if CONST_DOUBLE_LOW is positive, ensuring that 'unsigned long long'
variables are processed correctly during compiles. (BZ#465807)

• A bug in the way the GFortran compiler processed unique symtrees could

have prevented some valid GFortran code from compiling if the code
contained symbols defined by USE and ONLY clauses. Whenever this occurred,
the compile attempt would fail with a segmentation fault. This update adds
a special function that correctly reconciles symbols with unique symtrees,
which resolves this bug. (BZ#483845)

• Using the -fabi-version=1 option prevented some valid C++ code from

compiling. This was because Version 1 of the C++ ABI did not properly
substitute template parameters. This release corrects this behavior, adding
a function that correctly sets the processing_template_decl to 0 when
performing substitutions. (BZ#492011)

• A bug in the way gcc optimized code could have prevented some samples of

valid C code from compiling (resulting in an internal compiler error)
whenever the -O1 option was used. This was because during optimized
compiles, the C compiler did not properly process bounds; this resulted in
incorrect computations for loop iterations. With this update, the compiler
now processes bounds correctly, ensuring that valid C code compiles
correctly with the -O1 option set. (BZ#490513)

• The GFortran compiler did not handle FMT= character array arguments

properly. This prevented some samples of valid GFortran code from
compiling; whenever this occurred, the compile attempt would fail with a
segmentation fault. This update adds new functions to correct how FMT=
character array arguments are handled, thereby resolving this bug.
(BZ#492209)

• The expand_expr_real_1() function of the C compiler did not handle

TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR cases correctly. As a result, a
compile attempt could fail with an internal compiler error on the PowerPC
platform. This update applies an upstream fix for this issue. (BZ#495469)

Users are advised to upgrade to this gcc update, which applies these fixes.

Solution

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 465807 - [Regression] long long may not work correctly
• BZ - 483845 - gfortran segfaults on compilation of code
• BZ - 490211 - g++ error with -fabi-version=1
• BZ - 490513 - -O1 loop optimization bug
• BZ - 492209 - f95 fortran compiler fails with segfault
• BZ - 495469 - internal compiler error: in expand_expr_real_1, at expr.c:9199

CVEs

(none)

References

(none)