1 1.12 rillig # $NetBSD: directive-export.mk,v 1.12 2024/06/01 10:06:23 rillig Exp $ 2 1.1 rillig # 3 1.2 rillig # Tests for the .export directive. 4 1.6 rillig # 5 1.6 rillig # See also: 6 1.6 rillig # directive-misspellings.mk 7 1.1 rillig 8 1.1 rillig # TODO: Implementation 9 1.1 rillig 10 1.3 rillig INDIRECT= indirect 11 1.3 rillig VAR= value $$ ${INDIRECT} 12 1.3 rillig 13 1.5 rillig # Before 2020-12-13, this unusual expression invoked undefined behavior since 14 1.5 rillig # it accessed out-of-bounds memory via Var_Export -> ExportVar -> MayExport. 15 1.5 rillig .export ${:U } 16 1.5 rillig 17 1.3 rillig # A variable is exported using the .export directive. 18 1.3 rillig # During that, its value is expanded, just like almost everywhere else. 19 1.3 rillig .export VAR 20 1.3 rillig .if ${:!env | grep '^VAR'!} != "VAR=value \$ indirect" 21 1.3 rillig . error 22 1.3 rillig .endif 23 1.3 rillig 24 1.3 rillig # Undefining a variable that has been exported implicitly removes it from 25 1.3 rillig # the environment of all child processes. 26 1.3 rillig .undef VAR 27 1.3 rillig .if ${:!env | grep '^VAR' || true!} != "" 28 1.3 rillig . error 29 1.3 rillig .endif 30 1.3 rillig 31 1.12 rillig # Before var.c 1.1117 from 2024-06-01, a plain ".export" without a syntactical 32 1.12 rillig # argument exported all global variables. This case could be triggered 33 1.12 rillig # unintentionally by writing a line of the form ".export ${VARNAMES}" to a 34 1.12 rillig # makefile, when VARNAMES was an empty list. 35 1.12 rillig # expect+1: warning: .export requires an argument. 36 1.6 rillig .export 37 1.4 rillig 38 1.7 rillig # An empty argument means no additional variables to export. 39 1.7 rillig .export ${:U} 40 1.7 rillig 41 1.8 rillig 42 1.10 rillig # Before a child process is started, whether for the '!=' assignment operator 43 1.10 rillig # or for the ':sh' modifier, all variables that were marked for being exported 44 1.10 rillig # are expanded and then exported. If expanding such a variable requires 45 1.10 rillig # running a child command, the marked-as-exported variables would need to be 46 1.10 rillig # exported first, ending in an endless loop. To avoid this endless loop, 47 1.10 rillig # don't export the variables while preparing a child process, see 48 1.10 rillig # ExportVarEnv. 49 1.8 rillig EMPTY_SHELL= ${:sh} 50 1.8 rillig .export EMPTY_SHELL # only marked for export at this point 51 1.8 rillig _!= :;: # Force the variable to be actually exported. 52 1.8 rillig 53 1.8 rillig 54 1.9 rillig # If the '.export' directive exports a variable whose value contains a '$', 55 1.9 rillig # the actual export action is deferred until a subprocess is started, assuming 56 1.9 rillig # that only subprocesses access the environment variables. The ':localtime' 57 1.9 rillig # modifier depends on the 'TZ' environment variable, without any subprocess. 58 1.9 rillig export TZ=${UTC} 59 1.9 rillig # expect+1: 00:00:00 60 1.9 rillig .info ${%T:L:localtime=86400} 61 1.9 rillig INDIRECT_TZ= ${:UAmerica/Los_Angeles} 62 1.9 rillig TZ= ${INDIRECT_TZ} 63 1.9 rillig .export TZ 64 1.9 rillig # expect+1: 00:00:00 65 1.9 rillig .info ${%T:L:localtime=86400} 66 1.9 rillig _!= echo 'force exporting the environment variables' 67 1.9 rillig # expect+1: 16:00:00 68 1.9 rillig .info ${%T:L:localtime=86400} 69 1.9 rillig 70 1.9 rillig 71 1.1 rillig all: 72
Indexes created Sat Sep 20 22:09:52 GMT 2025