http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49401
Summary: Warning regression for 'uninitialized' variable on
non-existant code path (in mep-pragma.c)
Product: gcc
Version: 4.7.0
Status: UNCONFIRMED
Keywords: build, diagnostic
Severity: normal
Priority: P3
Component: other
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: amyl...@gcc.gnu.org
Blocks: 44756
Host: x86_64-unknown-linux-gnu
Created attachment 24517
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24517
Preprocessed source file
GCC 4.7.0 20110613 (experimental) (revision 174993) warns about a construct
in mep-pragma.c which was fine with 4.7.0 20110412. An if clause tests
if a variable is within a particular range, and then has a switch that
initialized another variable for each possible value of the first variable
in the tested-for range. GCC 4.7.0 20110613 now says that the second variable
might be uninitialized.
amylaar@gcc20:~/pr46489/jun13/multi2/mep-elf/gcc$
/home/amylaar/inst/20110412/libexec/gcc/x86_64-unknown-linux-gnu/4.7.0/cc1
-fpreprocessed mep-pragma.i -quiet -dumpbase mep-pragma.c -mtune=generic
-march=x86-64 -auxbase mep-pragma -g -O2 -Wextra -Wall -Wwrite-strings
-Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wmissing-format-attribute
-pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror
-Wold-style-definition -Wc++-compat -version -fno-common -o mep-pragma.s
GNU C (GCC) version 4.7.0 20110412 (experimental) (x86_64-unknown-linux-gnu)
compiled by GNU C version 4.7.0 20110412 (experimental), GMP version
4.3.2, MPFR version 3.0.0-p3, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
GNU C (GCC) version 4.7.0 20110412 (experimental) (x86_64-unknown-linux-gnu)
compiled by GNU C version 4.7.0 20110412 (experimental), GMP version
4.3.2, MPFR version 3.0.0-p3, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: 41657c4e14ab8d46a76879065321da34
amylaar@gcc20:~/pr46489/jun13/multi2/mep-elf/gcc$ echo $?
0
amylaar@gcc20:~/pr46489/jun13/multi2/mep-elf/gcc$
/home/amylaar/inst/20110613/libexec/gcc/x86_64-unknown-linux-gnu/4.7.0/cc1
-fpreprocessed mep-pragma.i -quiet -dumpbase mep-pragma.c -mtune=generic
-march=x86-64 -auxbase mep-pragma -g -O2 -Wextra -Wall -Wwrite-strings
-Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wmissing-format-attribute
-pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror
-Wold-style-definition -Wc++-compat -version -fno-common -o mep-pragma.s
GNU C (GCC) version 4.7.0 20110613 (experimental) (x86_64-unknown-linux-gnu)
compiled by GNU C version 4.7.0 20110613 (experimental), GMP version
4.3.2, MPFR version 3.0.0-p3, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
GNU C (GCC) version 4.7.0 20110613 (experimental) (x86_64-unknown-linux-gnu)
compiled by GNU C version 4.7.0 20110613 (experimental), GMP version
4.3.2, MPFR version 3.0.0-p3, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: 843a960cd48831f97b6a22dedb2d6c40
../../../gcc/gcc/config/mep/mep-pragma.c: In function ‘mep_pragma_coprocessor’:
../../../gcc/gcc/config/mep/mep-pragma.c:298:54: error: ‘rclass’ may be used
uninitialized in this function [-Werror=maybe-uninitialized]
../../../gcc/gcc/config/mep/mep-pragma.c:271:18: note: ‘rclass’ was declared
here
cc1: all warnings being treated as errors
