Build failure for usr.bin/printf

[Paul Goyette <paul%whooppee.com@localhost>]

With $SRCDIR updated on 2021-04-16 at 18:08:17 UTC I am seeing

...
#   compile  csh/printf.o
/build/netbsd-local/tools/x86_64/amd64/bin/x86_64--netbsd-gcc -O2   -fPIE  -g   -std=gnu99    -Wall -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Wno-sign-compare  -Wsystem-headers   -Wno-traditional   -Wa,--fatal-warnings  -Wreturn-type -Wswitch -Wshadow -Wcast-qual -Wwrite-strings -Wextra -Wno-unused-parameter -Wno-sign-compare -Wold-style-definition -Wconversion -Wsign-compare -Wformat=2  -Wno-format-zero-length  -Werror     --sysroot=/build/netbsd-local/dest/amd64 -I/build/netbsd-local/src_ro/bin/csh -I. -DBUILTIN -DFILEC -DNLS -DSHORT_STRINGS -DEDIT  -c -Wno-format-nonliteral   /build/netbsd-local/src_ro/usr.bin/printf/printf.c -o printf.o.o
/build/netbsd-local/src_ro/usr.bin/printf/printf.c: In function 'conv_escape':
/build/netbsd-local/src_ro/usr.bin/printf/printf.c:508:14: error: conversion from 'int' to 'char' may change value [-Werror=conversion]
  508 |    value <<= 3;
      |              ^
/build/netbsd-local/src_ro/usr.bin/printf/printf.c:122:21: error: conversion from 'int' to 'char' may change value [-Werror=conversion]
  122 | #define octtobin(c) (char)((c) - '0')
      |                     ^
/build/netbsd-local/src_ro/usr.bin/printf/printf.c:509:13: note: in expansion of macro 'octtobin'
  509 |    value += octtobin(*str);
      |             ^~~~~~~~
/build/netbsd-local/src_ro/usr.bin/printf/printf.c:522:14: error: conversion from 'int' to 'char' may change value [-Werror=conversion]
  522 |    value <<= 4;
      |              ^
/build/netbsd-local/src_ro/usr.bin/printf/printf.c:524:13: error: conversion from 'int' to 'char' may change value [-Werror=conversion]
  524 |    value += d;
      |             ^
cc1: all warnings being treated as errors
*** [printf.o] Error code 1
nbmake[7]: stopped in /build/netbsd-local/src_ro/bin/csh

+--------------------+--------------------------+-----------------------+
| Paul Goyette       | PGP Key fingerprint:     | E-mail addresses:     |
| (Retired)          | FA29 0E3B 35AF E8AE 6651 | paul%whooppee.com@localhost     |
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