build: Use own variable SECP_CFLAGS instead of touching user CFLAGS

Fixes one of the items in #923, namely the warnings of the form
    '_putenv' redeclared without dllimport attribute:
    previous dllimport ignored [-Wattributes]

This also cleans up the way we add CFLAGS, in particular flags enabling
warnings. Now we perform some more fine-grained checking for flag
support, which is not strictly necessary but the changes also help to
document autoconf.ac.
This commit is contained in:
Tim Ruffing
2021-05-13 17:06:16 +02:00
parent 1758a92ffd
commit 07256267ff
3 changed files with 62 additions and 41 deletions

View File

@@ -1,5 +1,9 @@
ACLOCAL_AMFLAGS = -I build-aux/m4
# AM_CFLAGS will be automatically prepended to CFLAGS by Automake when compiling some foo
# which does not have an explicit foo_CFLAGS variable set.
AM_CFLAGS = $(SECP_CFLAGS)
lib_LTLIBRARIES = libsecp256k1.la
include_HEADERS = include/secp256k1.h
include_HEADERS += include/secp256k1_preallocated.h
@@ -129,10 +133,10 @@ CPPFLAGS_FOR_BUILD +=-I$(top_srcdir) -I$(builddir)/src
gen_context_OBJECTS = gen_context.o
gen_context_BIN = gen_context$(BUILD_EXEEXT)
gen_%.o: src/gen_%.c src/libsecp256k1-config.h
$(CC_FOR_BUILD) $(DEFS) $(CPPFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) -c $< -o $@
$(CC_FOR_BUILD) $(DEFS) $(CPPFLAGS_FOR_BUILD) $(SECP_CFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) -c $< -o $@
$(gen_context_BIN): $(gen_context_OBJECTS)
$(CC_FOR_BUILD) $(CFLAGS_FOR_BUILD) $(LDFLAGS_FOR_BUILD) $^ -o $@
$(CC_FOR_BUILD) $(SECP_CFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) $(LDFLAGS_FOR_BUILD) $^ -o $@
$(libsecp256k1_la_OBJECTS): src/ecmult_static_context.h
$(tests_OBJECTS): src/ecmult_static_context.h